Question

Two supplementary angles are in the ratio 1 : 3. Find the angles.

• A. ${60}^{\circ }$ and ${120}^{\circ }$
• B. ${50}^{\circ }$ and ${130}^{\circ }$
• C. ${75}^{\circ }$ and ${115}^{\circ }$
• D. ${45}^{\circ }$ and ${135}^{\circ }$

Answer 1

The correct option is D ${45}^{\circ }$ and ${135}^{\circ }$

Let the first angle be x and second angle be 3x.
Sum of supplementary angles = ${180}^{\circ }$
x + 3x = ${180}^{\circ }$
4x = ${180}^{\circ }$
x = ${45}^{\circ }$
One angle is ${45}^{\circ }$ and the other angle is ${135}^{\circ }$.