Finding the Unknown Angle

Front

What is an angle?

Back

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

Front

What is the measure of a right angle?

Back

A right angle measures 90 degrees.

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 is a complete turn in degrees?

Back

A complete turn is 360 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

How do you find the unknown angle in a triangle?

Back

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

Front

What is a straight angle?

Back

A straight angle measures exactly 180 degrees.

Front

If one angle measures 30 degrees, what is the measure of its complement?

Back

The complement of a 30-degree angle is 60 degrees.

Front

If one angle measures 70 degrees, what is the measure of its supplement?

Back

The supplement of a 70-degree angle is 110 degrees.