Question

Which relation is a function?

Answer 1

The second one.

You can't have two numbers on a single line of y.

Answer 2

Graph B is a function

Explanation:

We can use the vertical line test to determine if a relation is a function. If a vertical line passes through more than one point, the relation is not a function.

Graph A At x=-1 a vertical line will pass through 3 points, so it is not a function.

Graph B A vertical line does not pass through more than 1 point

Graph C At x=2, it will pass through 2 points so it is not a function