The angle bisector, median, and altitude are all the same things in an isosceles triangle.
That means that the legs of the smaller triangles created by the altitude are 4 root 2.
By special properties of an right triangle, the hypotenuse is 8.
Since the legs of the original right triangle are congruent, the area of the original triangle is 8*8/2.
Now we just simplify:
8*8/2=64/2=32