Question

Which relations are functions?

Select Function or Not a function for each graph.

Answer 1

The first two are functions and the last two are not functions

Answer 2

The graphs that represent functions are the second and third graphs.

Which relations are functions?

When we have graphs of relationships, the easier way to identify if we have functions or not is with the vertical line test.

This test says that if can find a vertical line that intercepts the graph more than once, then we don't have a function.

With this test, we can see that the only two functions are the line and the cubic functions (first and second graph in the second image)