Question

If ABCD is a parallelogram with two adjacent angles $\angle A=\angle B$ then the parallelogram is a

(a) rhombus

(b) trapezium

(c) rectangle

(d) none of these

Answer 1

ANSWER:
(c) Rectangle
Explanation:
∠ A = ∠ B
Then ∠ A + ∠ B = ${180}^o$
⇒ 2 ∠ A = ${180}^o$
⇒ ∠ A ​ = ${90}^o$
⇒ ∠ A ​ =​ ∠ B ​ =​∠ C ​ =​​∠ D =${90}^o$
∴​ The parallelogram is a rectangle.