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4MA1/1F Jun 2025, Question 14: Substitution

Pearson Edexcel International GCSE Mathematics A 4MA1 · Paper 1F (Foundation) · Calculator · 5 marks

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The question, in short

Algebra tasks: expand a product, factorise an expression, and use a formula to find a when m = 48 and b = 3.

Summarised in our own words. Use the official paper for the exact wording and any diagrams.

Part (a) · 1 mark

Expand x(x − 7).

  1. 1x × x = x²
  2. 2x × (−7) = −7x
  3. 3x² − 7x

Answerx² − 7x

Part (b) · 1 mark

Factorise 8y − 10.

  1. 1HCF of 8y and 10 is 2
  2. 28y − 10 = 2(4y − 5)

Answer2(4y − 5)

Part (c) · 3 marks

Given m = 5a + 7b, work out a when m = 48 and b = 3.

  1. 148 = 5a + 7 × 3
  2. 248 = 5a + 21
  3. 35a = 48 − 21 = 27
  4. 4a = 27 ÷ 5
  5. 5a = 5.4

Answer5.4

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