Angle A and angle B are supplementary angles.

What must be true about the angles?

A. The sum of the angles is 90 degree

B. The sum of the angles is 180 degree

C. The angles were formed by two intersecting lines and are on opposite sides.

D. The angles share a common side and vertex.

Supplementary angles, when added, = 180 degrees ... ur answer is B

Solution:

As per the problem we have

Angle A and angle B are supplementary angles.

As we know that, two angles are supplementary angles if their sum is 180.

So when these two angles will be together on a plane will make a straight line.

Hence, when Angle A and angle B are supplementary angles.

Then

The sum of the angles is 180 degree.