Types of 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 are the types of angles based on their measures?

Back

Acute (less than 90°), Right (exactly 90°), Obtuse (greater than 90° but less than 180°), Straight (exactly 180°).

Front

What is a straight angle?

Back

A straight angle measures exactly 180 degrees and looks like a straight line.

Front

What is an acute angle?

Back

An acute angle measures less than 90 degrees.

Front

What is an obtuse angle?

Back

An obtuse angle measures more than 90 degrees but less than 180 degrees.

Front

What is a right angle?

Back

A right angle measures exactly 90 degrees.

Front

What are complementary angles?

Back

Two angles that add up to 90 degrees.

Front

What are supplementary angles?

Back

Two angles that add up to 180 degrees.

Front

What is a transversal line?

Back

A transversal is a line that intersects two or more lines at different points.

Front

What are alternate interior angles?

Back

Angles that are on opposite sides of the transversal and inside the two lines.