The equation is y = mx + b and m is the slope. You were already given the slope and you were even given a point. All you have to do is graph the point and use the slope until it intercepts the y-axis.
Plot the point (9,-8)
Go up 2, left 3 spots until the line hits the y-axis (the vertical one)
That point is what b will be equal to in y = mx + b
