Here is a simple set of slides created using Geogebra. I would normally just do this directly on Geogebra but as I needed to prepare some slides for our department planning, I thought I would share them. I have added some suggestions for how to run these in the notes section

I want students to make the connection that if the y-value doesn’t change for a bunch of coordinates (in this base the y-value is always 4) then the line that those coordinates all sit on is y=4. I’ve even made a little GIF where the point deliberately slides off the the right for a little while. Gotta love a GIF!

EQUATION OF STRAIGHT LINES

These slides are in groups of 4 designed to be used as a mini-whiteboard exercise for groups that need reinforcement on equations of the more basic straight-line graphs that can be determined by looking at patterns in the co-ordinates of points on the line (i.e. all points have a y-coordinate of -4 means the line is y=-4)

The idea is that you show the line itself first and ask students to show on their mini-whiteboards the equation of the line if they know it. If they don’t, then showing them the next slide with a bunch of co-ordinates provides the scaffolding. The next slide then reveals the equation and the final slide is to make the point that the coordinates themselves are arbitrary.

…with solutions on Geogebra Tube (click on the questions).

## Ideas for better maths teaching