Question

There are three angle formed at a point. If one of the angle is right angle, second angle is straight angle, then the third angle must be _____.

• A. Acute angle
• B. Obtuse angle
• C. Right angle
• D. Straight angle

Answer 1

Answer: (C)

Right angle

Given that one angle is right angle $={90}^{\circ }$

second is a straight angle $={180}^{\circ }$

Sum of angle at a point is ${360}^{\circ }$

The third angle is ${360}^{\circ }-({180}^{\circ }+{90}^{\circ })$

$={360}^{\circ }-{270}^{\circ }$

$={90}^{\circ }$

$={90}^{\circ }$ is a right angle.