In this instance, x=0. Do the same for x=1, x=2, x=3 and x=4. Image caption, STEP 3 - Draw a graph and label the x axis 1 to 4 and the y axis 1 to 9. A linear equation is represented as a line graph.

This means that, using Pythagoras’ theorem, the equation of a circle with radius \(r\) and centre (0, 0) is given by the formula \(x^2+ y^2= r^2\). Find the equation of a circle with radius 3 ...