A,B,C A, B, C\,A,B,C and D D\,D are points on the circumference of a circle, centre OOO.

Prove that angle ABD ABD\,ABD and angle ACD ACD\,ACD are equal.
Practise AQA GCSE Maths Proof of the Circle Theorems with exam-style questions for Foundation and Higher tier. 20 questions, matched to the AQA GCSE Maths (8300) specification and written in Paper 1, Paper 2 and Paper 3 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.