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2026 · test · Mathematics · Grade 11

Grade 11 Mathematics — class test (45 min)

Notes

Class test. Answer all four questions. Show a formula, substitution and answer with units.

60 min · 109 Marks · 30 questions

Learn the paper in the app: notes, a marks breakdown, the formula you need, and the board working. You do not need to download it.

Question breakdown

  1. 1 · 10 Marks · Exponents & surds

    √72 simplified

    -2-1012

    Formulas

    am/ⁿ=ⁿaᵐ

    Rational exponent

    √a·√b=ab

    Product of surds

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: √72 simplified

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 72 simplified. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: √72 simplified. Circle that word — that is the missing variable.

    Find

    We are required to find: √72 simplified. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: √72 = √(36×2) = 6√2. Then substitute the given, one line at a time, to get √72 simplified.

    In other words — as if you have never seen this before

    If you have never seen this before: √72 = √(36×2) = 6√2. We will name a method in words, write the formula with no numbers, then substitute one line at a time.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 72 simplified. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    √72=36×2=6√2.

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 72 simplified. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: √72 simplified. Circle that word — that is the missing variable. Find: We are required to find: √72 simplified. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: √72 = √(36×2) = 6√2. Then substitute the given, one line at a time, to get √72 simplified.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 72 simplified. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      √72=36×2=6√2.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      √72=36×2=6√2.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      6√2

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    6√2

    Copy onto your answer sheet — in this order

    Answer: 6√2

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  2. 2 · 10 Marks · Quadratic equations & nature of roots

    Nature of roots of x² + 6x + 9 = 0

    Formulas

    Δ=b²−4ac

    Discriminant

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Nature of roots of x² + 6x + 9 = 0

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 6x · 9 · 0. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: Nature of roots of x² + 6x + 9 = 0. Circle that word — that is the missing variable.

    Find

    We are required to find: Nature of roots of x² + 6x + 9 = 0. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: Δ = 36 − 36 = 0. Then substitute the given, one line at a time, to get Nature of roots of x² + 6x + 9 = 0.

    In other words — as if you have never seen this before

    If you have never seen this before: Δ = 36 − 36 = 0. Equal real rational roots; it is a perfect square (x+3)². We will name a method in words, write the formula with no numbers, then substitute one line at a time.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 6x · 9 · 0. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    Δ = 36 − 36 = 0. Equal real rational roots; it is a perfect square (x+3)².

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 6x · 9 · 0. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Nature of roots of x² + 6x + 9 = 0. Circle that word — that is the missing variable. Find: We are required to find: Nature of roots of x² + 6x + 9 = 0. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: Δ = 36 − 36 = 0. Then substitute the given, one line at a time, to get Nature of roots of x² + 6x + 9 = 0.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 6x · 9 · 0. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      Δ = 36 − 36 = 0. Equal real rational roots; it is a perfect square (x+3)².

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      Δ = 36 − 36 = 0. Equal real rational roots; it is a perfect square (x+3)².

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      real, rational, equal

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    real, rational, equal

    Copy onto your answer sheet — in this order

    Answer: real, rational, equal

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  3. 3 · 10 Marks · Identities, reduction & equations

    sin θ = 12 in [0°; 180°]

    hbθ

    Formulas

    sin²θ+cos²θ=1

    Pythagorean identity

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: sin θ = 12 in [0°; 180°]

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 1/ · 2 in · 0° · 180°. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: sin θ = 12 in [0°; 180°]. Circle that word — that is the missing variable.

    Find

    We are required to find: sin θ = 12 in [0°; 180°]. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: Sine is positive in Q1 and Q2. Then substitute the given, one line at a time, to get sin θ = 12 in [0°; 180°].

    In other words — as if you have never seen this before

    If you have never seen this before: Sine is positive in Q1 and Q2. Reference 30°. Q2: 180° − 30° = 150°. We will name a method in words, write the formula with no numbers, then substitute one line at a time.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 1/ · 2 in · 0° · 180°. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    Sine is positive in Q1 and Q2. Reference 30°. Q2: 180° − 30° = 150°.

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 1/ · 2 in · 0° · 180°. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: sin θ = 12 in [0°; 180°]. Circle that word — that is the missing variable. Find: We are required to find: sin θ = 12 in [0°; 180°]. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: Sine is positive in Q1 and Q2. Then substitute the given, one line at a time, to get sin θ = 12 in [0°; 180°].

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 1/ · 2 in · 0° · 180°. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      Sine is positive in Q1 and Q2. Reference 30°. Q2: 180° − 30° = 150°.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      Sine is positive in Q1 and Q2. Reference 30°. Q2: 180° − 30° = 150°.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      30° and 150°

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    30° and 150°

    Copy onto your answer sheet — in this order

    Answer: 30° and 150°

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  4. 4 · 10 Marks · Nominal vs effective interest

    12% p.a. compounded monthly. i per period =

    Formulas

    1+ieff=(1 + inom/m)m

    Effective rate

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: 12% p.a. compounded monthly. i per period =

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 12%. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: i per period =. Circle that word — that is the missing variable.

    Find

    We are required to find: i per period =. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: i = 0. Then substitute the given, one line at a time, to get i per period =.

    In other words — as if you have never seen this before

    If you have never seen this before: i = 0.1212=0.01. Nominal rate divided by number of periods per year. We will name a method in words, write the formula with no numbers, then substitute one line at a time.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 12%. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    i = 0.1212=0.01. Nominal rate divided by number of periods per year.

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 12%. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: i per period =. Circle that word — that is the missing variable. Find: We are required to find: i per period =. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: i = 0. Then substitute the given, one line at a time, to get i per period =.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 12%. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      i = 0.1212=0.01. Nominal rate divided by number of periods per year.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      i = 0.1212=0.01. Nominal rate divided by number of periods per year.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      0.01

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    0.01

    Copy onto your answer sheet — in this order

    Answer: 0.01

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  5. 5 · 3 Marks · Identities, reduction & equations

    cos θ = 0 in [0°; 360°]

    hbθ

    Formulas

    sin²θ+cos²θ=1

    Pythagorean identity

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: cos θ = 0 in [0°; 360°]

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 0 in · 0° · 360°. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: cos θ = 0 in [0°; 360°]. Circle that word — that is the missing variable.

    Find

    We are required to find: cos θ = 0 in [0°; 360°]. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: 90° and 270°. Then substitute the given, one line at a time, to get cos θ = 0 in [0°; 360°].

    In other words — as if you have never seen this before

    90° and 270°

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 0 in · 0° · 360°. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    90° and 270°

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 0 in · 0° · 360°. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: cos θ = 0 in [0°; 360°]. Circle that word — that is the missing variable. Find: We are required to find: cos θ = 0 in [0°; 360°]. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: 90° and 270°. Then substitute the given, one line at a time, to get cos θ = 0 in [0°; 360°].

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 0 in · 0° · 360°. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      90° and 270°

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      Cosine is the x-coordinate on the unit circle. x = 0 at the top (90°) and the bottom (270°).

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      90° and 270°

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    90° and 270°

    Copy onto your answer sheet — in this order

    Answer: 90° and 270°

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  6. 6 · 2 Marks · Exponents & surds

    √48 simplified

    -2-1012

    Formulas

    am/ⁿ=ⁿaᵐ

    Rational exponent

    √a·√b=ab

    Product of surds

    Notes: √48. Unknown: simplest surd form (no square factor left under the radical).

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: √48 simplified

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 48 simplified. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: √48 simplified. Circle that word — that is the missing variable.

    Find

    We are required to find: √48 simplified. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    Write 48 = 16 × 3 with empty letters. Cross out every letter that already has a number. Calculate the letter that is still standing — that gives √48 simplified.

    In other words — as if you have never seen this before

    Pull out the biggest square factor. 48 = 16 × 3, and 16 is 4².

    2. What do we already know?

    √48. Unknown: simplest surd form (no square factor left under the radical).

    3. Which method — and why this one?

    Pull out the biggest square factor. 48 = 16 × 3, and 16 is 4².

    4. Step-by-step working

    1. 01 / 05

      Factor 48

      48 = 16 × 3, and 16 is a perfect square. (You could use 4 × 12, but then you would simplify again.)

      48=16×3

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    2. 02 / 05

      Take the square out

      √48=16×3=√16×√3=4√3.

      √48=4√3

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    3. 03 / 05

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    4. 04 / 05

      Step F — Box the answer with its unit

      4√3

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    5. 05 / 05

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    4√3

    Copy onto your answer sheet — in this order

    Formula: 48=16×3

    Answer: 4√3

    6. Check it like a marker

    4√3 squared: 16 × 3 = 48. Lands back. 16√3 would square to a much bigger number.

    7. A trap first-timers fall into

    Stopping at √16 × √3 without taking √16. Or writing 3√4, which is not simplified (√4 is still 2).

  7. 7 · 2 Marks · Parabola, hyperbola & exponential

    x² − 5x + 6 < 0. Solution is

    Formulas

    y=a(x + p)²+q

    Shifted parabola

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: x² − 5x + 6 < 0. Solution is

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 5x · 6 · 0. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: Solution is. Circle that word — that is the missing variable.

    Find

    We are required to find: Solution is. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: Smile-parabola negative between roots 2 and 3. Then substitute the given, one line at a time, to get Solution is.

    In other words — as if you have never seen this before

    Smile-parabola negative between roots 2 and 3.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 5x · 6 · 0. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    Smile-parabola negative between roots 2 and 3.

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 5x · 6 · 0. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Solution is. Circle that word — that is the missing variable. Find: We are required to find: Solution is. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: Smile-parabola negative between roots 2 and 3. Then substitute the given, one line at a time, to get Solution is.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 5x · 6 · 0. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      Smile-parabola negative between roots 2 and 3.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      Smile-parabola negative between roots 2 and 3.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      (2; 3)

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    (2; 3)

    Copy onto your answer sheet — in this order

    Answer: (2; 3)

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  8. 8 · 4 Marks · Dependent events & Venn

    P(A)=0.3, P(B)=0.4, independent. P(A and B) =

    Formulas

    P(A ∪ B)=P(A)+P(B)−P(A ∩ B)

    Addition rule

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: P(A)=0.3, P(B)=0.4, independent. P(A and B) =

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 0.3 · 0.4. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: P(A and B) =. Circle that word — that is the missing variable.

    Find

    We are required to find: P(A and B) =. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: Independent: P(A∩B)=P(A)P(B)=0. Then substitute the given, one line at a time, to get P(A and B) =.

    In other words — as if you have never seen this before

    Independent: P(A∩B)=P(A)P(B)=0.12.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 0.3 · 0.4. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    Independent: P(A∩B)=P(A)P(B)=0.12.

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 0.3 · 0.4. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: P(A and B) =. Circle that word — that is the missing variable. Find: We are required to find: P(A and B) =. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: Independent: P(A∩B)=P(A)P(B)=0. Then substitute the given, one line at a time, to get P(A and B) =.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 0.3 · 0.4. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      Independent: P(A∩B)=P(A)P(B)=0.12.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      Independent: P(A∩B)=P(A)P(B)=0.12.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      0.12

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    0.12

    Copy onto your answer sheet — in this order

    Answer: 0.12

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  9. 9 · 3 Marks · Nominal vs effective interest

    R8000 depreciates at 10% p.a. reducing balance for 2 years. Value =

    Formulas

    1+ieff=(1 + inom/m)m

    Effective rate

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: R8000 depreciates at 10% p.a. reducing balance for 2 years. Value =

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: R8000 depreciates · 10% · 2 years. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: Value =. Circle that word — that is the missing variable.

    Find

    We are required to find: Value =. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: 8000(0. Then substitute the given, one line at a time, to get Value =.

    In other words — as if you have never seen this before

    8000(0.9)²=6480.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: R8000 depreciates · 10% · 2 years. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    8000(0.9)²=6480.

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: R8000 depreciates · 10% · 2 years. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Value =. Circle that word — that is the missing variable. Find: We are required to find: Value =. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: 8000(0. Then substitute the given, one line at a time, to get Value =.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: R8000 depreciates · 10% · 2 years. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      8000(0.9)²=6480.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      8000(0.9)²=6480.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      R6480

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    R6480

    Copy onto your answer sheet — in this order

    Answer: R6480

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  10. 10 · 2 Marks · Quadratic equations & nature of roots

    If second differences are constant, the pattern is

    Formulas

    Δ=b²−4ac

    Discriminant

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: If second differences are constant, the pattern is

    In other words — as if you have never seen this before

    Constant second difference ⇒ quadratic.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    Constant second difference ⇒ quadratic.

    4. Step-by-step working

    1. 01 / 07

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 07

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    3. 03 / 07

      Step C — Name the method in words

      Constant second difference ⇒ quadratic.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    4. 04 / 07

      Working

      Constant second difference ⇒ quadratic.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    5. 05 / 07

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    6. 06 / 07

      Step F — Box the answer with its unit

      quadratic

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    7. 07 / 07

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    quadratic

    Copy onto your answer sheet — in this order

    Answer: quadratic

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  11. 11 · 3 Marks · Nominal vs effective interest

    12% p.a. compounded monthly. Periods per year m =

    Formulas

    1+ieff=(1 + inom/m)m

    Effective rate

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: 12% p.a. compounded monthly. Periods per year m =

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 12%. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: Periods per year m =. Circle that word — that is the missing variable.

    Find

    We are required to find: Periods per year m =. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: 12. Then substitute the given, one line at a time, to get Periods per year m =.

    In other words — as if you have never seen this before

    12

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 12%. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    12

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 12%. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Periods per year m =. Circle that word — that is the missing variable. Find: We are required to find: Periods per year m =. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: 12. Then substitute the given, one line at a time, to get Periods per year m =.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 12%. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      12

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Reason

      Monthly → 12.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      12

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    12

    Copy onto your answer sheet — in this order

    Answer: 12

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  12. 12 · 2 Marks · Dependent events & Venn

    P(A or B) for mutually exclusive events

    Formulas

    P(A ∪ B)=P(A)+P(B)−P(A ∩ B)

    Addition rule

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: P(A or B) for mutually exclusive events

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: P(A or B) for mutually exclusive events. Circle that word — that is the missing variable.

    Find

    We are required to find: P(A or B) for mutually exclusive events. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: No overlap, so add. Then substitute the given, one line at a time, to get P(A or B) for mutually exclusive events.

    In other words — as if you have never seen this before

    No overlap, so add.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    No overlap, so add.

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: P(A or B) for mutually exclusive events. Circle that word — that is the missing variable. Find: We are required to find: P(A or B) for mutually exclusive events. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: No overlap, so add. Then substitute the given, one line at a time, to get P(A or B) for mutually exclusive events.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      No overlap, so add.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      No overlap, so add.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      P(A)+P(B)

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    P(A)+P(B)

    Copy onto your answer sheet — in this order

    Answer: P(A)+P(B)

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  13. 13 · 3 Marks · Identities, reduction & equations

    sin(180°−θ)=

    hbθ

    Formulas

    sin²θ+cos²θ=1

    Pythagorean identity

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: sin(180°−θ) =

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 180°. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: sin(180°−θ) =. Circle that word — that is the missing variable.

    Find

    We are required to find: sin(180°−θ) =. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: Reduction: Q2 sine is positive. Then substitute the given, one line at a time, to get sin(180°−θ) =.

    In other words — as if you have never seen this before

    Reduction: Q2 sine is positive.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 180°. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    Reduction: Q2 sine is positive.

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 180°. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: sin(180°−θ) =. Circle that word — that is the missing variable. Find: We are required to find: sin(180°−θ) =. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: Reduction: Q2 sine is positive. Then substitute the given, one line at a time, to get sin(180°−θ) =.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 180°. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      Reduction: Q2 sine is positive.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      Reduction: Q2 sine is positive.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      sin θ

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    sin θ

    Copy onto your answer sheet — in this order

    Answer: sin θ

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  14. 14 · 3 Marks · Proportion & midpoint theorem

    Midpoints of two sides of a triangle are joined. The third side is 10 cm. The join is

    hbθ

    Formulas

    DE ∥ BC, AD=DB⇒AE=EC

    Midpoint theorem

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Midpoints of two sides of a triangle are joined. The third side is 10 cm. The join is

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 10 cm. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: The join is. Circle that word — that is the missing variable.

    Find

    We are required to find: The join is. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: Midpoint theorem: half the third side. Then substitute the given, one line at a time, to get The join is.

    In other words — as if you have never seen this before

    Midpoint theorem: half the third side.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 10 cm. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    Midpoint theorem: half the third side.

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 10 cm. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: The join is. Circle that word — that is the missing variable. Find: We are required to find: The join is. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: Midpoint theorem: half the third side. Then substitute the given, one line at a time, to get The join is.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 10 cm. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      Midpoint theorem: half the third side.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      Midpoint theorem: half the third side.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      5 cm

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    5 cm

    Copy onto your answer sheet — in this order

    Answer: 5 cm

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  15. 15 · 4 Marks · Variance, ogives & five-number summary

    Five-number summary is

    -2-1012

    Formulas

    x̄=Σxn

    Mean

    σ²=Σ(x − x̄)²n

    Population variance (CAPS uses n)

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Five-number summary is

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: Five-number summary is. Circle that word — that is the missing variable.

    Find

    We are required to find: Five-number summary is. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: Box-and-whisker uses these five. Then substitute the given, one line at a time, to get Five-number summary is.

    In other words — as if you have never seen this before

    Box-and-whisker uses these five.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    Box-and-whisker uses these five.

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: no numbers yet — only a name, a diagram, or a worded unknown. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Five-number summary is. Circle that word — that is the missing variable. Find: We are required to find: Five-number summary is. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: Box-and-whisker uses these five. Then substitute the given, one line at a time, to get Five-number summary is.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: every number and its unit in the sentence. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      Box-and-whisker uses these five.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      Box-and-whisker uses these five.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      min, Q1, median, Q3, max

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    min, Q1, median, Q3, max

    Copy onto your answer sheet — in this order

    Answer: min, Q1, median, Q3, max

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  16. 16 · 2 Marks · Quadratic equations & nature of roots

    x² − 1 < 0 has solution

    Formulas

    Δ=b²−4ac

    Discriminant

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: x² − 1 < 0 has solution

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 1 · 0 has. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: x² − 1 < 0 has solution. Circle that word — that is the missing variable.

    Find

    We are required to find: x² − 1 < 0 has solution. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: Negative between the roots of (x−1)(x+1). Then substitute the given, one line at a time, to get x² − 1 < 0 has solution.

    In other words — as if you have never seen this before

    Negative between the roots of (x−1)(x+1).

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 1 · 0 has. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    Negative between the roots of (x−1)(x+1).

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 1 · 0 has. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: x² − 1 < 0 has solution. Circle that word — that is the missing variable. Find: We are required to find: x² − 1 < 0 has solution. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: Negative between the roots of (x−1)(x+1). Then substitute the given, one line at a time, to get x² − 1 < 0 has solution.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 1 · 0 has. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      Negative between the roots of (x−1)(x+1).

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      Negative between the roots of (x−1)(x+1).

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      −1 < x < 1

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    −1 < x < 1

    Copy onto your answer sheet — in this order

    Answer: −1 < x < 1

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  17. 17 · 2 Marks · Exponents & surds

    √18 simplified

    -2-1012

    Formulas

    am/ⁿ=ⁿaᵐ

    Rational exponent

    √a·√b=ab

    Product of surds

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: √18 simplified

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 18 simplified. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: √18 simplified. Circle that word — that is the missing variable.

    Find

    We are required to find: √18 simplified. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: √(9×2)=3√2. Then substitute the given, one line at a time, to get √18 simplified.

    In other words — as if you have never seen this before

    9×2=3√2.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 18 simplified. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    9×2=3√2.

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 18 simplified. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: √18 simplified. Circle that word — that is the missing variable. Find: We are required to find: √18 simplified. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: √(9×2)=3√2. Then substitute the given, one line at a time, to get √18 simplified.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 18 simplified. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      9×2=3√2.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      9×2=3√2.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      3√2

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    3√2

    Copy onto your answer sheet — in this order

    Answer: 3√2

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  18. 18 · 3 Marks · Proportion & midpoint theorem

    Angle at centre 120°. Angle at circumference on same arc

    hbθ

    Formulas

    DE ∥ BC, AD=DB⇒AE=EC

    Midpoint theorem

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Angle at centre 120°. Angle at circumference on same arc

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 120°. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: Angle at circumference on same arc. Circle that word — that is the missing variable.

    Find

    We are required to find: Angle at circumference on same arc. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: 60°. Then substitute the given, one line at a time, to get Angle at circumference on same arc.

    In other words — as if you have never seen this before

    60°

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 120°. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    60°

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 120°. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Angle at circumference on same arc. Circle that word — that is the missing variable. Find: We are required to find: Angle at circumference on same arc. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: 60°. Then substitute the given, one line at a time, to get Angle at circumference on same arc.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 120°. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      60°

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      Theorem: angle at the circumference is half the angle at the centre, standing on the same arc.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      60°

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    60°

    Copy onto your answer sheet — in this order

    Answer: 60°

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  19. 19 · 3 Marks · Nominal vs effective interest

    12% p.a. compounded quarterly. i per period =

    Formulas

    1+ieff=(1 + inom/m)m

    Effective rate

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: 12% p.a. compounded quarterly. i per period =

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 12%. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: i per period =. Circle that word — that is the missing variable.

    Find

    We are required to find: i per period =. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: 0. Then substitute the given, one line at a time, to get i per period =.

    In other words — as if you have never seen this before

    0.03

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 12%. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    0.03

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 12%. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: i per period =. Circle that word — that is the missing variable. Find: We are required to find: i per period =. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: 0. Then substitute the given, one line at a time, to get i per period =.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 12%. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      0.03

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Reason

      m=4. 0.124=0.03.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      0.03

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    0.03

    Copy onto your answer sheet — in this order

    Answer: 0.03

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  20. 20 · 3 Marks · Dependent events & Venn

    Independent P(A)=0.4, P(B)=0.5. P(A and B) =

    Formulas

    P(A ∪ B)=P(A)+P(B)−P(A ∩ B)

    Addition rule

    Notes: P(A) = 0.4, P(B) = 0.5, independent. Unknown: P(A ∩ B).

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Independent P(A)=0.4, P(B)=0.5. P(A and B) =

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 0.4 · 0.5. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: P(A and B) =. Circle that word — that is the missing variable.

    Find

    We are required to find: P(A and B) =. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    Write P(A ∩ B) = P(A)P(B) with empty letters. Cross out every letter that already has a number. Calculate the letter that is still standing — that gives P(A and B) =.

    In other words — as if you have never seen this before

    Independent means “one does not change the other.” Then P(A and B) = P(A) × P(B). Adding is “or” for mutually exclusive events.

    2. What do we already know?

    P(A) = 0.4, P(B) = 0.5, independent. Unknown: P(A ∩ B).

    3. Which method — and why this one?

    Independent means “one does not change the other.” Then P(A and B) = P(A) × P(B). Adding is “or” for mutually exclusive events.

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 0.4 · 0.5. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: P(A and B) =. Circle that word — that is the missing variable. Find: We are required to find: P(A and B) =. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: Write P(A ∩ B) = P(A)P(B) with empty letters. Cross out every letter that already has a number. Calculate the letter that is still standing — that gives P(A and B) =.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      P(A) = 0.4, P(B) = 0.5, independent. Unknown: P(A ∩ B).

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      Independent means “one does not change the other.” Then P(A and B) = P(A) × P(B). Adding is “or” for mutually exclusive events.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Multiply

      P(A ∩ B)=0.4×0.5=0.20.

      P(A ∩ B)=P(A)P(B)

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      0.20

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    0.20

    Copy onto your answer sheet — in this order

    Formula: P(A ∩ B)=P(A)P(B)

    Answer: 0.20

    6. Check it like a marker

    0.20 is smaller than both 0.4 and 0.5, as an “and” must be. 0.90 would be the “or” if they were mutually exclusive — they are not, and that was not asked.

    7. A trap first-timers fall into

    Adding 0.4+0.5=0.90. That is P(A or B) for mutually exclusive events, a different sentence.

  21. 21 · 2 Marks · Quadratic equations & nature of roots

    Nature of roots of x² + 4x + 4 = 0

    Formulas

    Δ=b²−4ac

    Discriminant

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Nature of roots of x² + 4x + 4 = 0

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 4x · 4 · 0. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: Nature of roots of x² + 4x + 4 = 0. Circle that word — that is the missing variable.

    Find

    We are required to find: Nature of roots of x² + 4x + 4 = 0. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: real, rational, equal. Then substitute the given, one line at a time, to get Nature of roots of x² + 4x + 4 = 0.

    In other words — as if you have never seen this before

    real, rational, equal

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 4x · 4 · 0. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    real, rational, equal

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 4x · 4 · 0. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Nature of roots of x² + 4x + 4 = 0. Circle that word — that is the missing variable. Find: We are required to find: Nature of roots of x² + 4x + 4 = 0. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: real, rational, equal. Then substitute the given, one line at a time, to get Nature of roots of x² + 4x + 4 = 0.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 4x · 4 · 0. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      real, rational, equal

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Reason

      Δ=0, perfect square.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      real, rational, equal

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    real, rational, equal

    Copy onto your answer sheet — in this order

    Answer: real, rational, equal

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  22. 22 · 3 Marks · Quadratic equations & nature of roots

    First differences of a quadratic with a=2. Second difference =

    Formulas

    Δ=b²−4ac

    Discriminant

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: First differences of a quadratic with a=2. Second difference =

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 2. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: Second difference =. Circle that word — that is the missing variable.

    Find

    We are required to find: Second difference =. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: 2a = second difference = 4. Then substitute the given, one line at a time, to get Second difference =.

    In other words — as if you have never seen this before

    2a = second difference = 4.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 2. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    2a = second difference = 4.

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 2. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Second difference =. Circle that word — that is the missing variable. Find: We are required to find: Second difference =. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: 2a = second difference = 4. Then substitute the given, one line at a time, to get Second difference =.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 2. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      2a = second difference = 4.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      2a = second difference = 4.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      4

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    4

    Copy onto your answer sheet — in this order

    Answer: 4

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  23. 23 · 2 Marks · Identities, reduction & equations

    Area of triangle a=6, b=5, included angle 30°

    hbθ

    Formulas

    sin²θ+cos²θ=1

    Pythagorean identity

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Area of triangle a=6, b=5, included angle 30°

    In other words — as if you have never seen this before

    ½ab sin C=½×6×5×0.5=7.5.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 6 · 5 · 30°. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    ½ab sin C=½×6×5×0.5=7.5.

    4. Step-by-step working

    1. 01 / 07

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 07

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 6 · 5 · 30°. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    3. 03 / 07

      Step C — Name the method in words

      ½ab sin C=½×6×5×0.5=7.5.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    4. 04 / 07

      Working

      ½ab sin C=½×6×5×0.5=7.5.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    5. 05 / 07

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    6. 06 / 07

      Step F — Box the answer with its unit

      7.5

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    7. 07 / 07

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    7.5

    Copy onto your answer sheet — in this order

    Answer: 7.5

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  24. 24 · 4 Marks · Variance, ogives & five-number summary

    Five scores: 2, 4, 4, 6, 9. Mean is

    -2-1012

    Formulas

    x̄=Σxn

    Mean

    σ²=Σ(x − x̄)²n

    Population variance (CAPS uses n)

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Five scores: 2, 4, 4, 6, 9. Mean is

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 2 · 4 · 4 · 6 · 9. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: Mean is. Circle that word — that is the missing variable.

    Find

    We are required to find: Mean is. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: Σx = 25, n = 5, mean = 5. Then substitute the given, one line at a time, to get Mean is.

    In other words — as if you have never seen this before

    Σx=25, n=5, mean=5.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 2 · 4 · 4 · 6 · 9. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    Σx=25, n=5, mean=5.

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 2 · 4 · 4 · 6 · 9. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Mean is. Circle that word — that is the missing variable. Find: We are required to find: Mean is. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: Σx = 25, n = 5, mean = 5. Then substitute the given, one line at a time, to get Mean is.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 2 · 4 · 4 · 6 · 9. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      Σx=25, n=5, mean=5.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      Σx=25, n=5, mean=5.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      5

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    5

    Copy onto your answer sheet — in this order

    Answer: 5

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  25. 25 · 2 Marks · Exponents & surds

    √50 simplified is

    -2-1012

    Formulas

    am/ⁿ=ⁿaᵐ

    Rational exponent

    √a·√b=ab

    Product of surds

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: √50 simplified is

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 50 simplified. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: √50 simplified is. Circle that word — that is the missing variable.

    Find

    We are required to find: √50 simplified is. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: √50 = √(25×2) = 5√2. Then substitute the given, one line at a time, to get √50 simplified is.

    In other words — as if you have never seen this before

    √50=25×2=5√2.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 50 simplified. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    √50=25×2=5√2.

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 50 simplified. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: √50 simplified is. Circle that word — that is the missing variable. Find: We are required to find: √50 simplified is. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: √50 = √(25×2) = 5√2. Then substitute the given, one line at a time, to get √50 simplified is.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 50 simplified. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      √50=25×2=5√2.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      √50=25×2=5√2.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      5√2

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    5√2

    Copy onto your answer sheet — in this order

    Answer: 5√2

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  26. 26 · 2 Marks

    Δ for x² − 5x + 6 = 0

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Δ for x² − 5x + 6 = 0

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 5x · 6 · 0. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: Δ for x² − 5x + 6 = 0. Circle that word — that is the missing variable.

    Find

    We are required to find: Δ for x² − 5x + 6 = 0. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: 1. Then substitute the given, one line at a time, to get Δ for x² − 5x + 6 = 0.

    In other words — as if you have never seen this before

    1

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 5x · 6 · 0. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    1

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 5x · 6 · 0. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Δ for x² − 5x + 6 = 0. Circle that word — that is the missing variable. Find: We are required to find: Δ for x² − 5x + 6 = 0. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: 1. Then substitute the given, one line at a time, to get Δ for x² − 5x + 6 = 0.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 5x · 6 · 0. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      1

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      Δ = b² − 4ac = 25 − 24 = 1. Positive perfect square → two real rational unequal roots.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      1

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    1

    Copy onto your answer sheet — in this order

    Answer: 1

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  27. 27 · 2 Marks

    2⁴=

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: 2⁴ =

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 2. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: 2⁴ =. Circle that word — that is the missing variable.

    Find

    We are required to find: 2⁴ =. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: 2×2×2×2 = 16. Then substitute the given, one line at a time, to get 2⁴ =.

    In other words — as if you have never seen this before

    2×2×2×2=16.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 2. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    2×2×2×2=16.

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 2. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: 2⁴ =. Circle that word — that is the missing variable. Find: We are required to find: 2⁴ =. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: 2×2×2×2 = 16. Then substitute the given, one line at a time, to get 2⁴ =.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 2. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      2×2×2×2=16.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      2×2×2×2=16.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      16

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    16

    Copy onto your answer sheet — in this order

    Answer: 16

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  28. 28 · 3 Marks · Nominal vs effective interest

    12% p.a. compounded monthly. Monthly interest rate i =

    Formulas

    1+ieff=(1 + inom/m)m

    Effective rate

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: 12% p.a. compounded monthly. Monthly interest rate i =

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 12%. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: Monthly interest rate i =. Circle that word — that is the missing variable.

    Find

    We are required to find: Monthly interest rate i =. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: i = 0. Then substitute the given, one line at a time, to get Monthly interest rate i =.

    In other words — as if you have never seen this before

    i=0.1212=0.01.

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 12%. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    i=0.1212=0.01.

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 12%. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Monthly interest rate i =. Circle that word — that is the missing variable. Find: We are required to find: Monthly interest rate i =. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: i = 0. Then substitute the given, one line at a time, to get Monthly interest rate i =.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 12%. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      i=0.1212=0.01.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Working

      i=0.1212=0.01.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      0.01

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    0.01

    Copy onto your answer sheet — in this order

    Answer: 0.01

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

  29. 29 · 2 Marks · Parabola, hyperbola & exponential

    y=−x²+4. Maximum y=

    Formulas

    y=a(x + p)²+q

    Shifted parabola

    Notes: A downward parabola. Vertex on the y-axis.

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: y = −x² + 4. Maximum y =

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 4. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: Maximum y =. Circle that word — that is the missing variable.

    Find

    We are required to find: Maximum y =. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    Write y = 4 with empty letters. Cross out every letter that already has a number. Calculate the letter that is still standing — that gives Maximum y =.

    In other words — as if you have never seen this before

    Coefficient of x² is negative, so a maximum. It is the +4.

    2. What do we already know?

    A downward parabola. Vertex on the y-axis.

    3. Which method — and why this one?

    Coefficient of x² is negative, so a maximum. It is the +4.

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 4. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Maximum y =. Circle that word — that is the missing variable. Find: We are required to find: Maximum y =. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: Write y = 4 with empty letters. Cross out every letter that already has a number. Calculate the letter that is still standing — that gives Maximum y =.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      A downward parabola. Vertex on the y-axis.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      Coefficient of x² is negative, so a maximum. It is the +4.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Read q

      Completed square already: max = 4 at x = 0.

      y=4

      Why this step: Write the formula before numbers. The memo awards a method mark even if a digit slips later.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      4

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    4

    Copy onto your answer sheet — in this order

    Formula: y=4

    Answer: 4

    6. Check it like a marker

    At x=0, y=4. At x=1, y=3, lower.

    7. A trap first-timers fall into

    −4 would be if the square were added with a plus in front of x².

  30. 30 · 3 Marks · Proportion & midpoint theorem

    Angle at circumference is 36°. Angle at centre on same arc

    hbθ

    Formulas

    DE ∥ BC, AD=DB⇒AE=EC

    Midpoint theorem

    How we got there

    Read this like a teacher at the board. We go slowly, name every number, and say why we take each step.

    Explain in another language · 11

    1. What is the question asking?

    Read the question twice. Circle the unknown. Underline every number and unit. The paper is asking: Angle at circumference is 36°. Angle at centre on same arc

    Before any working — hunt first

    Given

    Numbers and units already in the sentence: 36°. Copy each one into a column. A name without a number is not given.

    Missing

    After you copy the given, the letter that still has no number is missing. The paper is pointing at: Angle at centre on same arc. Circle that word — that is the missing variable.

    Find

    We are required to find: Angle at centre on same arc. Write that as a symbol on the left, with a question mark, before you touch a formula.

    Calculate

    What we need to calculate: 72°. Then substitute the given, one line at a time, to get Angle at centre on same arc.

    In other words — as if you have never seen this before

    72°

    2. What do we already know?

    Copy these onto the left of your page, one per line, with units: 36°. Mixing cm with m, or minutes with seconds, loses a method mark.

    3. Which method — and why this one?

    72°

    4. Step-by-step working

    1. 01 / 08

      Step A — Read the question twice

      Slow down. Circle the word that names the unknown. Underline every number and its unit. Do not grab a formula yet — first decide what the paper is actually asking.

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    2. 02 / 08

      Step A2 — Hunt: Given, Missing, Find, Calculate

      Given: Numbers and units already in the sentence: 36°. Copy each one into a column. A name without a number is not given. Missing: After you copy the given, the letter that still has no number is missing. The paper is pointing at: Angle at centre on same arc. Circle that word — that is the missing variable. Find: We are required to find: Angle at centre on same arc. Write that as a symbol on the left, with a question mark, before you touch a formula. Calculate: What we need to calculate: 72°. Then substitute the given, one line at a time, to get Angle at centre on same arc.

      Why this step: Do not name the letters yet. First hunt: what already has a number (Given), what has no number (Missing), the word the paper wants (Find), and which formula still contains the missing letter (Calculate).

    3. 03 / 08

      Step B — Write the given in a column

      Copy these onto the left of your page, one per line, with units: 36°. Mixing cm with m, or minutes with seconds, loses a method mark.

      Why this step: A column with units stops you mixing cm with m, or minutes with seconds. Markers can also see you started correctly.

    4. 04 / 08

      Step C — Name the method in words

      72°

      Why this step: If you can say the method in a sentence, you will pick the right formula. First-timers skip this and grab the first equation they remember.

    5. 05 / 08

      Reason

      Double.

      Why this step: We only do one job per line so a marker can follow the marks — and so you can find a slip without starting over.

    6. 06 / 08

      Step G — Sense-check the size

      Ask: is this the kind of number a Grade 10–12 paper would want? A speed of 3 000 ms for a learner walking, or a probability bigger than 1, means a unit or algebra slip. Estimate first: round the numbers and do the sum in your head.

      Why this step: Markers write ‘unrealistic’ in the margin when the method is right but the size is wild. A 10-second head check often finds a missing 10² or a unit that never changed.

    7. 07 / 08

      Step F — Box the answer with its unit

      72°

      Why this step: A number without a unit is half a mark on a Physics paper, and a marker can miss a Maths answer that is buried in working.

    8. 08 / 08

      Step H — What the marker is looking for

      On an NSC memo you usually earn: (1) a method mark for naming the right formula or idea in words, (2) an accuracy mark for substituting the given numbers with units, (3) an accuracy mark for the boxed answer with its unit. Write those three lines even if you are unsure of the arithmetic — blank pages score zero.

      Why this step: First-timers chase the final number and leave the method blank. The memo still pays out for the idea and the substitution even when the last line is wrong.

    5. The answer

    72°

    Copy onto your answer sheet — in this order

    Answer: 72°

    6. Check it like a marker

    Does your answer appear as one of the options? Do the units match what was asked (m, N, J, °)? If you put the number back into the original equation, does it still hold? Estimate: is the size sensible?

    7. A trap first-timers fall into

    First-timers often grab the first formula they remember, mix units (cm with m, minutes with seconds), or drop a minus sign. Write the formula in words first: “this equals that, because…”

Ntsako · fx-991ZA PLUS. Tap to calculate.