Question

Which table represents a function?

A 2-column table with 4 rows. The first column is labeled x with entries negative 3, 0, negative 2, 8. The second column is labeled y with entries negative 1, 0, negative 1, 1.

A 2-column table with 4 rows. The first column is labeled x with entries negative 5, 0, negative 5, 6. The second column is labeled y with entries negative 5, 0, 5, negative 6.

A 2-column table with 4 rows. The first column is labeled x with entries negative 4, negative 2, negative 2, 0. The second column is labeled y with entries 8, 2, 4, 2.

A 2-column table with 4 rows. The first column is labeled x with entries negative 4, 3, 1, negative 4. The second column is labeled y with entries 2, 5, 3, 0.

Answer 1

A function must have one y-value for any given x-value.

Usually, if you see the same x-value in the x-column more than once, that's not going to be a function, because that usuall makes a single x-value pair with more than one y-value.

This would be NOT be a function, because x-value of 3 is paired with two different y-values.

x | y

3 7

4 8

3 9

6 7

Can you identify the function?