Question

Help me please! Really stuck. Will Medal and Fan! Please check attachment.

Answer 1

If DE is congruent to FE, then it is an isosceles triangle. In an Isosceles triangle, both base angles are congruent. Since there are two right angles formed by line EG, you can tell that with 2 of both angles given of each individual triangles, the third from both are going to be congruent. (Due to the third angle is going to add up to 180 etc.)

Since both triangles have the same angles, the also have the same side lenghts

Hope this helps! ~