ECZ 2012 · O-Level Paper 1 — Circle Theorems
In the diagram, A, B and C are points on the circumference of a circle with centre O. AT and TB are tangents to the circle, angle CAO = 30 degrees and angle CBO = 29 degrees. Calculate angle ACB.
- A. 30 degrees
- B. 29 degrees
- C. 59 degrees
- D. 118 degrees
Verified working — step 1
OA = OC and OB = OC are radii, so triangles AOC and BOC are isosceles: angle ACO = 30 degrees and angle BCO = 29 degrees. Angle ACB = 30 + 29 = …The full step-by-step working and final answer are included with Premium — checked against ECZ marking standards.
Original examination question © Examinations Council of Zambia. Worked solution and commentary © G12 Titan — not to be reproduced without permission.
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