Answer:
100 cm^2
Explanation:
if FA and BF are the same and the shape is a square then the right triangles
FBC and FEC have the same area. FA is 1/2 the length of the square.
if you rotate FEC to the bottom of the square the shaded are will be 1/2 of the square. 50 = 1/2 of the square... unshaded left square = 50 , and 50 = unshaded on the right
total unshaded should be 100 cm^2