Student Tutorial: Geometry Basics: Parallel and Perpendicular Lines

Instructions:

Learn about parallel and perpendicular lines. For this tutorial you'll be using the Desmos Geometry Tools, which are free: https://www.desmos.com/geometry. Watch the video and follow along using the Desmos tools.

Click the arrows on the bottom to get started

Math Clip Art: Student Tutorial Title Page

Parallel Lines. Two coplanar lines that don’t intersect. In Coordinate Geometry, the graphs of two linear functions with the same slope.

Perpendicular Lines Two coplanar lines that intersect at right angles. In Coordinate Geometry, the graphs of two linear functions with slopes that are negative reciprocals.

Parallel and Perpendicular Lines Title Card

Whenever lines intersect, they form four angles.

Here are the four angles.

There is one case where two lines don’t form any angles. This is the case where the lines are parallel.

Line L is parallel to line M.

Two lines are parallel if they are coplanar and don’t intersect.

Parallel lines never touch, no matter how long the lines are.

Parallel lines are always the same distance apart.

Perpendicular lines intersect at right angles.

Line L is perpendicular to Line M.

Perpendicular lines form four 90° angles.