Plot points with coordinates where \(x\) and \(y\) are equal. Three points are sufficient, but more can be plotted. Draw a line through the plotted points. If \(x\) is positive, \(y\) is negative. If ...

The straight line through two points will have an equation in the form \(y = mx + c\). We can find the value of \(m\), the gradient of the line, by forming a right-angled triangle using the ...