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0580/42 May/Jun 2025, Question 18: Combining Circle Theorems

Cambridge IGCSE Mathematics 0580 · Paper 42 (Extended) · Calculator · 4 marks

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The question, in short

Using a circle through A, B, C, D and E with intersecting chords EB and AC, work out the sizes of angles x, y and z from the given 125°, 26° and 52°.

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

Solution · 4 marks

  1. 1In the triangle formed by E, C and the crossing point: x = 180 − 125 − 26 = 29
  2. 2y = angle AEB = angle ACB = 52 (angles in the same segment)
  3. 3Angle EBC = 180 − 29 − (26 + 52) = 73 (angles in triangle EBC)
  4. 4z = 180 − 73 = 107 (opposite angles of cyclic quadrilateral EBCD)
  5. 5x = 29, y = 52, z = 107

Answerx = 29, y = 52, z = 107

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Also searched as: 0580/42/M/J/25 · 0580_s25_qp_42 · 0580 s25 42 · question 18.
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