Question

The angle(s) which is/are supplementary to itself is/are -

• A. Zero degree
• B. ${45}^o$
• C. Right angle
• D. Straight angle

Answer 1

The correct option is C Right angle

The pair of angles that add up to ${180}^o$ are called supplementary angles.

Consider an angle $x.$

Given: $x$ is supplementary to itself.
$\therefore x+x={180}^o$
$\Rightarrow 2x={180}^o$
$\Rightarrow x=\frac{{180}^o}{2}={90}^o$

Hence, a right angle is supplementary to itself.
This is the only possible answer.