Area is 96 inches because we needed to separate the triangles. After we got the big one we were missing the shortest side so to find that we use Pythagorean theorem. We get 16^2+x=20^2
400-256=144
Sq root of 144 is 12.
Now that we found all the missing sides. Let find area 1/2*b*h
16*12/2=96