Question

six graphs are shown below. click on the tabs to see them.
graph 1 graph 2 graph 3 graph
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 this diamond-shaped graph, a vertical line (e.g., $x=0.5$) intersects the graph at two points, violating the test.

Answer:

This graph does NOT represent a function.