Question 1092803
There are two things I see:
first, the y and x values are differently scaled.  I would plot them using the same intervals between consecutive integers.
second, the parabola plotted does not go below one single point.  The plots should at least include points on both sides of the curve.  If this is a parabolic equation, it needs to be shifted downward.  The best plot of any function minimizes least square distances between the points and the function.  This plot if anything maximizes the differences.