If ABCD is square and both AED and CDF are equilateral tria

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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


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by Max@Math Revolution » Mon Mar 14, 2016 5:04 pm
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


-> Angle ADC=90 degrees, angle DEC=angle DCE=angle DFA=angle DAF=15 degrees. Then, angle DCF=60 degrees and angle GFC=45 degrees, which makes angle G=60 degrees. Therefore, the answer is C.