Basic Angle Relationships

Front

What is the definition of complementary angles?

Back

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

Front

What is the definition of supplementary angles?

Back

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

Front

What are vertical angles?

Back

Vertical angles are the angles opposite each other when two lines intersect. They are always equal.

Front

If angle A is 30 degrees, what is the measure of its complementary angle?

Back

60 degrees (90 - 30 = 60).

Front

If angle B is 120 degrees, what is the measure of its supplementary angle?

Back

60 degrees (180 - 120 = 60).

Front

What is the relationship between two angles that add up to 180 degrees?

Back

They are supplementary.

Front

What is the relationship between two angles that add up to 90 degrees?

Back

They are complementary.

Front

If two angles are vertical, what can we say about their measures?

Back

They are equal.

Front

If angle 1 is 45 degrees and angle 2 is 135 degrees, what is the relationship between them?

Back

They are supplementary.

Front

If angle 3 is 70 degrees, what is the measure of its complementary angle?

Back

20 degrees (90 - 70 = 20).