Angle Relationships

Front

What are vertical angles?

Back

Vertical angles are angles that are opposite each other when two lines intersect. They are always congruent.

Front

What does it mean for angles to be complementary?

Back

Complementary angles are two angles whose measures add up to 90 degrees.

Front

If angle A measures 30 degrees, what is the measure of angle B if they are complementary?

Back

Angle B measures 60 degrees.

Front

What does it mean for angles to be supplementary?

Back

Supplementary angles are two angles whose measures add up to 180 degrees.

Front

If two angles are supplementary and one measures 120 degrees, what is the measure of the other angle?

Back

The other angle measures 60 degrees.

Front

What is an example of a pair of complementary angles?

Back

81° and 9° are complementary angles because they add up to 90 degrees.

Front

Are the angles 45° and 45° complementary, supplementary, or neither?

Back

They are supplementary because they add up to 90 degrees.

Front

What is the sum of the measures of two supplementary angles?

Back

The sum of the measures of two supplementary angles is 180 degrees.

Front

What are adjacent angles?

Back

Adjacent angles are two angles that share a common side and a common vertex.

Front

If angle C measures 70 degrees, what is the measure of angle D if they are supplementary?

Back

Angle D measures 110 degrees.