Question

&
if one angle of a parallelogram is
a right angle, then it is necessarily?​

Answer 1

$\bold\pink{Answer}$

If one angle of a parallelogram is a right angle, then it is a rectangle. Because of this theorem, the definition of a rectangle is sometimes taken to be 'a parallelogram with a right angle'.....❤

Answer 2

then it is necessarily a rectangle

and then if all the sides are equal then it is a square