## IGD: Dropping a Perpendicular Line

Grade:

9-12

Standards:

Math Content:

Geometry

Constructing a line perpendicular to a given line and through a point not on the line is one of the most important constructions in geometry. This process is known as

*dropping a perpendicular*, because a perpendicular line is "dropped" from the point to the line.*How to Use*

· Use the points on the **sliders** to adjust the radii of the circles.

· You can drag points to change the location and orientation of the construction.

*Buttons*

The buttons will appear sequentially.

The **Reset** button will
allow you to start over.

- Construct a proof of this construction. If you
need a hint, click on the
**Hint- Why It Works**button at the end of the construction. - Where do you see perpendicular lines in real-life.
- Create a scenario where you would need to drop a perpendicular line from a specific point.

### IGD: Perpendicular Bisector

9-12

Use this tool to demonstrate how to draw a perpendicular bisector.