In circle C - I need to find AC, AB, FE and angle DAE.
I'm not sure how to solve it because I got confused by the teacher.
is C the center? (so the radius would be 10)?
if so, AC = AG + GC, where GC is the radius
we can find AB using Pythagoras' theorem
to find FE, you can draw a line from F to C and from E to C. note that you will form an isosceles triangle, with the angle at the center = 90 degrees. i think you can take it from there
to find angle DAE ... i have to think about some more. there seems to be some useful theorem that i'm forgetting at the moment