Let's put it this way: If you plot a few non-x-intercept points and then draw a curvy line through them,you will not know if you got the x-intercepts even close to being correct. <span>The only way you can be sure of your x-intercepts is to set the quadratic equal to zero and solve. So its a matter of guessing from the pictures. Basicaly said, the calculator won't give you the exact result.</span>