Points, Lines, Line Segments, Rays, and Angles

Front

What is a line?

Back

A straight set of points that goes on forever in both directions.

Front

What is a ray?

Back

A part of a line that starts at one point and goes on forever in one direction.

Front

What is a line segment?

Back

A part of a line between two endpoints.

Front

What are parallel lines?

Back

Lines that never meet and are always the same distance apart.

Front

What are perpendicular lines?

Back

Lines that intersect at a right angle (90 degrees).

Front

What is an angle?

Back

A figure formed by two rays with a common endpoint called the vertex.

Front

What is an acute angle?

Back

An angle that is less than 90 degrees.

Front

What is a right angle?

Back

An angle that is exactly 90 degrees.

Front

What is an obtuse angle?

Back

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

Front

What is a straight angle?

Back

An angle that is exactly 180 degrees.