a test to see if it is a function is a vertical line test, if you draw a straight line and the line intersects at 2 points, it is not a function.
in this case, (-2,-2) is an open hole, which means the value where it is placed is just around that value so not exact.
the vertical line test would work if it was a closed hole, and one or both points (-2,3) and (-2,-2) would have to be removed.
the mistake that deshawn made was that he mixed up the vertical line test with horizontal instead and has deduced that since a horizontal line has intercepted both points, they must be removed.
this graph is, in fact, a function since the open hole is not exactly under (-2,3)
