Paper 1 · Algebra ⏱ Tested in 5 exam questions since 2025 Lesson 14 of 23

Algebra 14 – Manipulation of formula

In this lesson you’ll learn to

  • Rearrange a formula by fixing one 'immediate complication' at a time
  • Square or cube both sides to clear roots when changing the subject
  • Clear fractions by multiplying by the denominator, then isolate the target
  • Use DOTS — x² − y² = (x − y)(x + y) — to dodge long expansions

Most recent exam questions

  • 2025 Paper 1 Q10(d)(i) — simple equation rearrangement
  • 2025 Paper 1 Q10(d)(ii) — algebraic substitution + simplification; the (a + b)² = a² + 2ab + b² expansion
  • 2025 Paper 1 Q6(b) — discriminant condition for a quadratic with equal roots
  • 2025 Paper 1 Q8(b) — solving an algebraic equation modelled from a contextual word problem
  • 2025 Paper 1 Q8(e)(i) — assembling a total-time function from two right-triangle distance pieces
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