Explore changing the values of m and c in the equations y=mx + c for each of the lines. What stays the same and what changes?[br]Can you make your lines parallel to each other? What do you notice about the gradients?[br]Can you make your lines perpendicular to each other? What do you notice about the gradients?[br]Set the red line to be [color=#c51414]y=x[/color], make the blue line perpendicular[br]Set the red line to be [color=#c51414]y=2x[/color], make the blue line perpendicular[br]If the red line was [color=#c51414]y=3x[/color] what would the gradient be of a perpendicular line? (not you cannot do this here as the sliders only increase in 0.1s)

[color=#0a971e]Created by NTrubridge[/color]