Paper 2 · Co-ordinate Geometry of the Line ⏱ Tested in 5+ recent exam questions Lesson 5 of 9

The line 5: Perpendicular distance from a point to a line

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You’ll learn

  • Find the distance from a point to a line with d = |ax₁ + by₁ + c|/√(a² + b²)
  • Rearrange the line to ax + by + c = 0 first, watching the sign of c
  • Solve for unknowns like k by splitting |X| = k into ± cases
  • Find two parallel lines a set distance away, or a point midway between parallel lines

Most recent exam questions

  • 2026 P2 Q4(c)
  • 2025 P2 Q1(b) — deferred
  • 2025 P2 Q6(b)(i) — deferred
  • 2024 P2 Q6(b)
  • 2023 P2 Q4(a)(ii)

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