4th Grade: Unknown Angles

Front

What is an angle?

Back

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

Front

What is the vertex of an angle?

Back

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

Front

What are the different types of angles?

Back

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

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 more 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

How do you measure an angle?

Back

An angle is measured in degrees using a protractor.

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 complementary angle?

Back

Complementary angles are two angles whose measures add up to 90 degrees.