Lines and Angles Vocabulary

Front

What is a line?

Back

A line is a straight path that extends infinitely in both directions.

Front

What is an acute angle?

Back

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

Front

What are perpendicular lines?

Back

Perpendicular lines are two lines that intersect to form at least one 90 degree angle.

Front

What is a horizontal line?

Back

A horizontal line is a line that runs from left to right.

Front

What is a right angle?

Back

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

Front

What is a ray?

Back

A ray is a part of a line that has a fixed starting point and extends infinitely in one direction.

Front

What is a line segment?

Back

A line segment is a part of a line that has two endpoints.

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 are parallel lines?

Back

Parallel lines are lines that never intersect and are always the same distance apart.

Front

What is a straight angle?

Back

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