In the diagram below, BC = QR = x, AC = PR=y, and triangle PQR is a right triangle. Use the drop-down menus to complete the proof that if the equation x2 + y2 = z2 is true of the side lengths in triangle ABC, then triangle ABC must be a right triangle. Choose(1)...
x2=y2, x2+y2=PQ2, x2+y2=PR2, x2+y2=1

Choose(2)...
x2=y2 and x=y, z2=PQ2 and z=PQ

Choose(3)...
<P=<B, <P=<A, <C=<R, <C=<Q