In the original graph, R (0,3), S(3,3), T(4, -1) and Q(0, 1) Reflecting it across y=-1, which is a horizontal line going through the point T, all the x coordinates stay the same, the new confidantes are : R'(0, -5), S'(3, -5), T'(4, -1), Q(0', -3) (Notice; T stays where it is now, because it is right now the line y=-1) Locate these new points, you have your graph.
An exact "zero" of a polynomial is characterized by a point on the x-axis. In this case the best approximation to that is the point (3/2, 0+); the next best approximation is (-1, 0+). Note that neither of these two points actually lies on the x-axis, but that both are closer to the x-axis than are any of the other given points.
