CPM Homework Help : GC Problem 9-80

Segment with points from left to right labeled, A,D,B,E, additional segments, A C, E F, C B, & F D, Segments C B & D F intersect at point labeled G. Examine the diagram at right. Given that $ΔABC ≅ ΔEDF$ , prove that $ΔDBG$ is isosceles. Use any format of proof that you prefer.

Hint:

If $ΔABC≅ΔEDF$ , then $∠EDF≅∠ABC$ .