The area of an equilateral triangle (A ft2) is equal to that of a square. What is the length of the diagonal of the square?

A. (2A) ft

B. A ft

C. (3A) ft

D. 2(A) ft

E. (5A) ft

I know how to get there, but not sure if it's a correct path (i.e. is there a better way to solve it.)

Forget the triangle, the area of both = A, and for the square A=s^2

Length of a diagonal of a square is S*2

Which we can see is A*2=(2A)