Any equation in the form
Is a line. So, we only need to sample two points, and then connect them.
If we choose, for example, x=0 and x=3, we have
So, when x=0 then y=0, i.e. the line passes through the origin (0,0).
Similarly, when x=3 then y=2, i.e. the line passes through the point (3,2).
Connect these two points and you have the line.
