Question

Two angles are supplementary. The first angle measures 60°. What's the measurement of the second angle?

Answer 1

Answer: Option D

120°

Step-by-step explanation:

By definition it is said that two A and B angles are supplementary if the sum of A and B is equal to 180 °

In this case we know that one of the angles is 60 °

This is: A = 60 °

So to find the second angle we propose the following equation:

$60\° + B = 180\°$

Then we solve the equation for B.

$B = 180\°-60\°$

$B = 120\°$

So the second angle is 120 °

The answer is option D

Answer 2

Answer:

D

Step-by-step explanation:

The sum of supplementary angles is 180°

To find the supplement of 60° subtract it from 180°, that is

second angle = 180° - 60° = 120° → D