# Perpendicular Lines

- Author:
- GeoGebra Materials Team

- Topic:
- Linear Functions

You can manipulate Lines 1 and 2 by moving the corresponding sliders. Please answer the questions below.

(1.) Leave the sliders for Line 2 as is. Move the sliders for Line 1 until the two lines are perpendicular. Do you see a relationship between the equations of the two lines?
(2.) Move the sliders for Line 2 so that the equation is y = 2x - 1. Move the sliders for Line 1 until the two lines are perpendicular. Do you see the same relationship as you did in #1?
(3.) Make a general conclusion about the relationship of the equations of perpendicular lines.
(4.) Move the sliders for Line 2 so that the equation is y = 4x - 1. Make a prediction as to what the equation of Line 1 should be so that the two lines are perpendicular. Test your prediction.
(5.) Move the sliders for Line 2 so that the equation is y = 3x - 1. Make a prediction as to what the equation of Line 1 should be so that the two lines are perpendicular. Test your prediction. Can you find any perpendicular line? Why or why not?