Angles on a Protractor

Front

What is an angle?

Back

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

Front

What is a protractor used for?

Back

A protractor is a tool used to measure angles in degrees.

Front

What is the measure of a right angle?

Back

A right angle measures 90 degrees.

Front

What is the measure of a straight angle?

Back

A straight angle measures 180 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 read a protractor?

Back

To read a protractor, align the baseline of the protractor with one side of the angle and read the measurement where the other side crosses the numbered scale.

Front

What is the measure of a 45-degree angle?

Back

A 45-degree angle is an acute angle that is half of a right angle.

Front

What is the measure of a 160-degree angle?

Back

A 160-degree angle is an obtuse angle that is close to a straight angle.

Front

What is the measure of a 100-degree angle?

Back

A 100-degree angle is an obtuse angle.