Measuring Angles

Front

What is an angle?

Back

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

Front

What is the vertex of an angle?

Back

The vertex of an angle is the point where the two rays meet.

Front

What are the different types of angles based on their measures?

Back

The different types of angles are acute (less than 90°), right (exactly 90°), obtuse (greater than 90° and less than 180°), straight (exactly 180°), reflex (greater than 180°), and full rotation (360°).

Front

What is an acute angle?

Back

An acute angle is an angle that measures less than 90 degrees.

Front

What is a right angle?

Back

A right angle is an angle that measures exactly 90 degrees.

Front

What is an obtuse angle?

Back

An obtuse angle is an angle that measures greater than 90 degrees but less than 180 degrees.

Front

What is a straight angle?

Back

A straight angle is an angle that measures exactly 180 degrees.

Front

What is a reflex angle?

Back

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

Front

What is the sum of angles in a triangle?

Back

The sum of the interior angles in a triangle is always 180 degrees.

Front

How do you measure an angle using a protractor?

Back

To measure an angle using a protractor, align the protractor's baseline with one ray of the angle, and read the measurement where the other ray intersects the protractor's scale.