ECZ 2018 · O-Level Paper 1 — Circle Theorems

In the diagram below, O is the centre of the circle. A, B, C and D are points on the circumference. AD produced meets the line from C at E such that CD = DE and angle AOC = 120°. Calculate angle (c) DEC.

Diagram for ECZ 2018 · O-Level Paper 1
  • A. 120°
  • B. 60°
  • C. 30°
  • D. 45°

Verified working — step 1

angle ADC = 60°.

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Original examination question © Examinations Council of Zambia. Worked solution and commentary © G12 Titan — not to be reproduced without permission.

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