Watch this video to learn about the equation of a straight line. Since we are given 2 points that already lie on the line, using the formula as before, we need to calculate the gradient first.

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 ...