Question

Which relation is not a function?

Answer 1

Step-by-step explanation: In order for a function not to be a relation,

each x-coordinate must correspond to more than one y-coordinate.

Notice that in third relation, the 1 pairs with a 3

in one case  and it pairs with a 7 in the other case.

Since each x-coordinate pairs with more than one y-coordinate,

this relation is not a function but the other ones are functions.

Answer 2

Answer: C

Step-by-step explanation:

The X value repeats itself