Question

if the diagonal of a parallelogram are equal then show that is rectangle

Answer 1

by using vector algebra this is the easiest algebric process i know till

Answer 2

rectangle is also a parallelogram . draw the figure with diagnals. consider the triangles n prove they are congruent. then by CPCTC (corresponding parts of congruent triangles) conclude that the diagnals are equal.. therefore it's a rectangle as well as parallelogram