Measuring Angles

Front

What is an angle?

Back

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

Front

What tool is used to measure angles?

Back

A protractor is 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 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 is a straight angle?

Back

A straight angle measures exactly 180 degrees.

Front

How do you read a protractor?

Back

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

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 reflex angle?

Back

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

Front

What is the measure of a full rotation?

Back

A full rotation measures 360 degrees.