One way to test if a graph is a function or not is by doing a vertical line test.
The vertical line test is tested by testing if any vertical line is drawn would intersect the curve more than once. If there is any such line, the graph does not represent a function, if there isn't any such line, the graph is a function.
Hope that helps!
Answer:
Vertical line test. (literally what it say)
Step-by-step explanation:
Given a graph, use the vertical line test to determine if the graph represents a function. Inspect the graph to see if any vertical line drawn would intersect the curve more than once.
Therefore you would have x value being the same for several points.
