### Home > CC3 > Chapter 9 > Lesson 9.1.1 > Problem 9-13

9-13.

Determine whether the graphs below are functions or not functions. Explain your reasoning. Homework Help ✎

a.

b.

c.

d.

e.

f.

A graph is only a function if there is no more than one *y*-value for any given *x*-value.

Are there any points on this line segment that are above or below another point on the line segment? If there are, the graph is not a function.

This graph is a function.

See hint for part (a).

This graph is not a function. Some *x*-values are related to multiple *y* values. For example, when *x* is 3, *y* can be 2 or ≈ 2.

See hint for part (a).

See hint for part (a).

See hint for part (a).

This graph is not a function.

See hint for part (a).