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4MA1/1F Jan 2020, Question 21: Solving Linear Equations

Pearson Edexcel International GCSE Mathematics A 4MA1 · Paper 1F (Foundation) · Calculator · 9 marks

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The question, in short

Four short algebra tasks: expand a product of brackets, factorise an expression fully, simplify a power-zero term, and solve an equation showing algebraic working.

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

Part (a) · 2 marks

Expand the product of the two brackets (m − 8)(m + 5) and simplify the result.

  1. 1Multiply each term: m × m, m × 5, −8 × m, −8 × 5
  2. 2m² + 5m − 8m − 40
  3. 3Collect like terms: m² − 3m − 40

Answerm² − 3m − 40

Part (b) · 2 marks

Factorise 5y + 20y² completely, taking out all common factors.

  1. 1The common factor of 5y and 20y² is 5y
  2. 25y ÷ 5y = 1 and 20y² ÷ 5y = 4y
  3. 35y(1 + 4y)

Answer5y(1 + 4y)

Part (c) · 1 mark

Simplify the expression (p² + 3)⁰.

  1. 1Any non-zero number to the power 0 is 1
  2. 2(p² + 3)⁰ = 1

Answer1

Part (d) · 4 marks

Solve 3(2x − 5) = (9 − x)/2 for x, showing clear algebraic working.

  1. 1Multiply both sides by 2: 6(2x − 5) = 9 − x
  2. 2Expand: 12x − 30 = 9 − x
  3. 3Add x and 30 to both sides: 13x = 39
  4. 4x = 39 ÷ 13 = 3

Answer3

Stuck on a step? Read the free lesson: Solving Linear Equations

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