Two-Point Graphing Method

A method of graphing a linear equation uses the Y-Intercept and the slope to create a line. Use a third point to check your work.

For example, if you want to plot $f(x)=2x+1$, the Y-intercept is to calculate $f(0)=1$ which is the height of the function at cero. The slope is the coefficient that multiply x, which in this case is 2. A third point could be evaluate at $x=1$ to obtain $f(1)=3$. So you have two positions in the cartesian plane: $(0, 1)$ and $(1,3)$, which determine an unique line of slope 2.