Question

six graphs are shown below. click on the tabs to see them.
graph 1 graph 2 graph 3 graph 4
check the box corresponding to each graph that represents a function.

Explanation:

To determine if a graph represents a function, use the Vertical Line Test: any vertical line drawn on the graph should intersect it at most once. For Graph 1, every vertical line crosses the line at exactly one point, so it passes the test.

Answer:

Graph 1 represents a function (check its corresponding box).