MathRevolution wrote:

Attachment:

ABCD.jpg

If ABCD is square and both AED and CDF are equilateral triangles, what is the angle FGC?

A. 45o

B. 50o

C. 60o

D. 75o

E. 80o

* A solution will be posted in two days.

Not sure if my approach is right .But here is what I thought.

Given ABCD is a square , AD,DC,AE,ED,DF,FC all are equal.

So EC and AF should be equal as angles ADE and CDF are both 60 each.

In the original AED construct all are 60 each.

angle AED = angle AEG + angle GED

or loss of angle GED is gained by angle GAD in the triangle .

as everything got balanced , angle EDA should be angle EGA or angle FGC => 60

Answer is C