Graph the points and plug in the numbers for the linear equation y=mx+b, where m is the slope of the line and b is the y-intercept. The y-intercept of this line is the value of y at the point where the line crosses the y axis. You can see that 1/-4 is the slope of the line and that the y-intercept is at (0,0). Plug in the number, and you get y=1/-4x+0.
