The y-intercept is at (0,8), so you can graph that point. Then the slope is -3/5. So the change in y coordinate divide the change in x coordinate is always -3/5. Thus 8-y/0-x=-3/5. You can choose any value for y and x as long as 8-y=-3. And 0-x=5. The point on the graph will just be (x,y) for the values you find.
