so the -1 is the y-intercept form. so you need to start at that point on the y axis. then the slope which is -1/2 comes into play. in my school we use rise/run. so from the point you marked at -1 you will go down 1 and to the right 2 points then where you stop is your next point (mark it) keep doing that. also go up the other way from the -1 point. go up 1 and to the left 2. then connect all of your points with a line. I hope this helped.
