Question

If $ABCD$ is a rhombus such that $\angle ACB={40}^o$, then $\angle ADB$ is

• A. ${40}^o$
• B. ${45}^o$
• C. ${50}^o$
• D. ${60}^o$

Answer 1

Answer: (C)

${50}^o$

Given:

$ABCD$ is a rhombus.

Its diagonal $AC$ and $BD$ interect at $O$.

$\angle ACB={40}^o$

We know that the angles subtended by one side of a rhombus at two opposite adjacent corners are complementary to eachother.

$\therefore \angle ACB+\angle ADB={90}^o$

$\Rightarrow \angle ADB={90}^o-{40}^o={50}^o$

Hence, option C.