This applet shows six animated lines, generated from three numbers, [math]a[/math], [math]b[/math], and [math]c[/math]. The lines are [math]ax + by = c[/math], [math]ax + cy = b[/math], etc.
There are a number of patterns and relationships between these lines, several of which are hinted at in the questions on the bottom of the student worksheet.
This is one of a several 'starter pictures' that I use as students are coming into my lessons, in order to motivate discussion and exploration. It can also be used as part of revision lessons on straight line graphs.
