Can you draw perpendicular lines without using a protractor?
Investigate how this is possible.
Investigate the positions of points which have particular x and y
coordinates. What do you notice?
This interactivity allows you to sort letters of the alphabet into two groups according to different properties.
At the time of writing the hour and minute hands of my clock are at
right angles. How long will it be before they are at right angles
Position the lines so that they are perpendicular to each other.
What can you say about the equations of perpendicular lines?
Can you decide whether two lines are perpendicular or not? Can you
do this without drawing them?