Finding Missing Angles

Front

What is an angle?

Back

An angle is formed by two rays (sides) that share a common endpoint (vertex). It is measured in 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 measures less than 90 degrees.

Front

What is an obtuse angle?

Back

An obtuse angle 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 a missing angle in a triangle?

Back

The sum of the angles in a triangle is always 180 degrees. To find a missing angle, subtract the sum of the known angles from 180.

Front

What is the measurement of the missing angle if two angles are 60 degrees and 50 degrees?

Back

The missing angle is 70 degrees (180 - (60 + 50)).

Front

What is the measurement of the missing angle if one angle is 90 degrees and another is 45 degrees?

Back

The missing angle is 45 degrees (180 - (90 + 45)).

Front

What is the sum of angles in a quadrilateral?

Back

The sum of angles in a quadrilateral is always 360 degrees.

Front

What is the measurement of the missing angle in a quadrilateral if three angles are 90, 80, and 70 degrees?

Back

The missing angle is 120 degrees (360 - (90 + 80 + 70)).