Answer: Since a vertical does pass through more than one point, the graph fails the vertical line test. So, the relation is not a function.
Explanation:
The "vertical line test" is used to determine if a graph represents a function. A function cannot have more than one output, so if more than one point touches a vertical line at any point on the graph, then that graph does not represent a function.
For example, if I drew a vertical line at x = 8, then two points would be touching the line: (8, -2) and (8, 2). Since the vertical line touches more than one point, it fails the vertical line test meaning that this graph does not represent a function.