Answer: Not a Function
Step-by-step explanation: For a function, each x term
must correspond to exactly one y term.
We can use the vertical line test to determine whether
or not that holds true for the graph shown here.
If each x term corresponds to exactly one y term, then any vertical line
that we draw on the graph should hit the graph at only one point.
Notice below that many of the vertical lines that we draw
on this graph will hit the graph at more than one point.
Thus, we can conclude that no, the graph shown here is not a function.