Question

A parallelogram is a rectangle if and only
if its diagonals are congruent.

Answer 1

It is a rhombus.Hope this helps

Answer 2

A parallelogram is a rectangle if and only if its diagonals are congruent. A rectangle is a parallelogram with four right angles. A rhombus is a parallelogram with four congruent sides. If a parallelogram has two consecutive sides congruent, it is a rhombus.

Explanation: