Question

If one pair of adjacent sides of a parallelogram is congruent, then the parallelogram must be a __________.

I thought it was rhombus or a square because all of their sides are equal in length, but I have to pick ONE.
A rectangle
B square
C rhombus

Answer 1

It must be a rhombus, because that's the parallelogram with all sides equal.

It could be a square, but it doesn't have to be. A square is a rhombus
with special angles.