construct-angle-f-so-that-m-angle-f-equals-2-m-angle-c

Answer 1

Given angle c, ACB

construct a circle with center C intersecting AC at D and CB at E.

Using D as a center, construct a circle with radius DE so it intersects the circle C at F.

Angle FCA = ACB since they subtend equal arcs.

So, FCB = FCA+ACB = 2*ACB