That is an equation in Slope Intercept Form. On your test, you would graph this. You would start at your Y- Intercept (4) on the y axis and then go up and to the right because your slope (3) is positive. If there is no denominator under your slope, then you put one there by simply just putting it over one. Then On your graph, start at your Y- Intercept (4) and go 3 lines up and one line to the right.