Angle Relationships

Front

What is an angle?

Back

An angle is formed by two rays (sides) that share a common endpoint (vertex).

Front

What is the sum of angles in a triangle?

Back

The sum of the angles in a triangle is always 180 degrees.

Front

What are complementary angles?

Back

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

Front

What are supplementary angles?

Back

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

Front

What is a right angle?

Back

A right angle measures exactly 90 degrees.

Front

What is an acute angle?

Back

An acute angle is an angle that measures less than 90 degrees.

Front

What is an obtuse angle?

Back

An obtuse angle is an angle that measures more than 90 degrees but less than 180 degrees.

Front

What is a straight angle?

Back

A straight angle measures exactly 180 degrees.

Front

How do you find the measure of a missing angle in a triangle?

Back

To find the missing angle, subtract the sum of the known angles from 180 degrees.

Front

If two angles are complementary and one angle measures 30 degrees, what is the measure of the other angle?

Back

The other angle measures 60 degrees (90 - 30 = 60).