In the Linear Equations quizzes you practised solving equations using algebra. This GCSE Maths quiz should help you understand the link between the algebra and the geometry of the straight line.
When a straight line is plotted on an x-y grid there are two key features that we can obtain, which will allow us to write down the equation of the straight line. This equation is the rule that connects the x- and the y-values.
The first feature is the gradient, which is a measure of how steep the line is. Recall that the gradient is ‘change in height over change in distance’. To calculate the gradient, plot two points on the line that pass directly through the crosshairs of the grid.