hi there!
a. the SSS theorem can be used to prove these two right triangles are congruent because they share one side, so that HAS to be congruent, the other sides are 25 inches each, so those sides are congruent, and when you solve the equations (x = 3/2) and plug it back in, both of the bottom sides are congruent as well because they equal seven.
b. the perimeter of the triangle GEF is 64 inches. this can be found by doing 2(7) + 2(25) = 64