Question

if the diagnals of paralellogram are equal then show that it is a rectangle

Answer 1

To prove :ABCD is a rectangle.Proof :InAB = DC [Opp. sides of a || gm]BC = BC [Common]and AC = DB [Given]Therefore, by SSS criterion of congruence. ... (1)[Corresponding parts of congruent triangles are equal]But AB || DC and BC cuts them.Therefore, ... (2) [Sum of consecutive interiorangles is 180°] Thus, ABCD is a parallelogram oneof whose angle is 90º .Hence , ABCD is a rectangle