I am doing practise papers and there is one question I cannot understand even with the mark scheme. I have added the pictures below:
Question (with added annotations):
The question is to find angle x (23 degrees, apparently).
At first I thought that angle OCD might be 69 degrees because of the alternate angle theorem, but I realised that it wasn't on a tangent so that wouldn't work. Other than that I have no idea - could someone please explain (in detail if possible, maths isn't my strength!) the steps to find it? Thanks in advance!