Question

If one of the angle of parallelogram is 90° then all the other angles are equal to .

• A. 75°
• B. 135°
• C. 45°
• D. 90°

Answer 1

The correct option is D 90°

Given that,
One of the angle of a parallelogram is 90°
Let ABCD be parallelogram and let $\angle A=90°$$\angle A+\angle B=180°$
[Adjacent angles of a parallelogram are supplementary]
$⟹90°+\angle B=180°$
$\therefore \angle B=90°$
Also, $\angle A=\angle C$ and $\angle B=\angle D$
[Opposite angles of a parallelogram are equal]
$\therefore \angle A=\angle B=\angle C=\angle D=90°$