Geometry Vocabulary

Front

What are complementary angles?

Back

Two angles that add up to 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 are supplementary angles?

Back

Two angles that add up to 180 degrees.

Front

What is a right angle?

Back

An angle that measures exactly 90 degrees.

Front

What is a straight angle?

Back

An angle that measures exactly 180 degrees.

Front

What is a reflex angle?

Back

A reflex angle is an angle that measures more than 180 degrees but less than 360 degrees.

Front

What is a full rotation in degrees?

Back

A full rotation is 360 degrees.

Front

What is the sum of angles in a triangle?

Back

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

Front

What is a vertical angle?

Back

Vertical angles are the angles opposite each other when two lines intersect, and they are equal.