Geometry Stumper

[Thomas Puettmann]

You do not even need to consider the right angle at C. In my first sketch, I drew it, but it is not neccessary for the argument.

Once you know that the line DC is the angular bisector of the exterior angles at C, you are done (by symmetry, the line EC is the same angular bisector).

Buy two, get one free, thanks to the circle at D.