Answer:
Point the point on the graph (3,-7) by find 3 on the x axis (horizontal line) and than going down -7 coordinates. and then start plotting points that are at a slope of 1/3 so you would go up 1 from the point (3,-7) and than go 3 right and then plot a point, and keep doing that to make a lot of points that create a straight line at the end when you connect them!
hope it helped!