Question

can a parallelogram be a rectangle?​

Answer 1

A rectangle is considered a special case of a parallelogram because: A parallelogram is a quadrilateral with 2 pairs of opposite, equal and parallel sides. A rectangle is a quadrilateral with 2 pairs of opposite, equal and parallel sides BUT ALSO forms right angles between adjacent sides.

Answer 2

It's not the case that "a parallelogram is never considered a rectangle". Some
parallelograms are rectangles, and some are not. But you cannot say in general that "every parallelogram is a rectangle", which is what would normally be meant by "an (arbitrary) parallelogram is a rectangle".

Hope this will help you