Angle Relationships

Front

What is an acute angle?

Back

An angle that is less than 90°.

Front

What are complementary angles?

Back

Angles that add up to 90°.

Front

What is the measure of a right angle?

Back

90°.

Front

What is an obtuse angle?

Back

An angle that is greater than 90° but less than 180°.

Front

If m∡1 = 118°, what is m∡5?

Back

118°.

Front

If m∡3 = 81°, what is m∡6?

Back

81°.

Front

What is a straight angle?

Back

An angle that measures exactly 180°.

Front

What are vertical angles?

Back

Angles that are opposite each other when two lines intersect; they are equal.

Front

What are supplementary angles?

Back

Angles that add up to 180°.

Front

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

Back

60°.