If an equation can be rearranged into the form \(y = mx + c\), then its graph will be a straight line. In the above: \(x + y = 3\) can be rearranged as \(y = 3 – x\) (which can be re-written as ...

There are several basic facts and equations connected with straight lines that you need to know by heart. We can calculate the gradient of the line above by selecting two coordinate points that ...