CPM Homework Help : CC3MN Problem 9-42

Identify which of the relationships shown below is not a function. Explain your reasoning.

$x$
x column 1 $3$
x column 2 $8$
x column 3 $1$
x column 4 $9$
x column 5 $–1$
x column 6 $0$
$y$
y column 1 $12$
y column 2 $4$
y column 3 $0$
y column 4 $4$
y column 5 $–3$
y column 6 $–8$
$x$
x column 1 $5$
x column 2 $2$
x column 3 $–1$
x column 4 $0$
x column 5 $–15$
x column 6 $2$
$y$
y column 1 $2$
y column 2 $0$
y column 3 $–11$
y column 4 $8$
y column 5 $–25$
y column 6 $1$

Hint:

A relationship is a function only if there is no more than one $y$ -value for each $x$ -value. Check the $x$ -values in both tables to see to find any that appear multiple times. When you find a value for $x$ that appears multiple times, check the corresponding $y$ -values. If the $y$ -values are different, then the relationship is not a function.

Answer:

Relationship (b) is not a function. When $x$ equals $2$ , $y$ can equal $0$ or $1$ .