All the others are 90 degrees too
Step-by-step explanation:
In a parallelogram opposite angles are congruent. Also in a quadrilateral the sum of angles is 360 degrees. since their are two pairs of congruent angles you could make an equation and it would look like this: 180+2x =360. x would be 90 making every angle 90 degrees.
Hope it helps :)❤
