Question

A parallelogram has one angle that measures 90° what are the measures of the other three

Answer 1

The other angles will be 90 degree.

Answer 2

Let as assume |_A is 90

• Sum of adjacent angles of a parallelogram is equal to 180.

|_A + |_B = 180

90 + |_B = 180

|_B = 180 - 90

|_B = 90

• Opposite angles of a parallelogram is equal.
|_A = |_C = 90

|_B = |_D = 90

Since , all angles are 90 it's a square !!