Proving the converse of the Pythagorean theorem means that when____ for a triangle ABC with____ of a, b, and c, triangle ABC___
a. vertices
b. angles
c. side lengths
d. (a+b)²=c²
e. a^2* b²=c²
f. a^2+b²=c²
g. is always a right triangle
h. is never a right triangle