Question

Which relation describes a function?

{(0,0), (0, 2), (2.0), (2, 2)}
{(-2, -3), (-3, -2), (2,3), (3, 2)}
{(2,-1), (2, 1), (3,-1), (3, 1)}
{(2, 2), (2, 3), (3, 2), (3, 3)}

Answer 1

The function is b) {(-2,-3), (-3,-2), (2,3), (3,2)}

Answer 2

{(-2, -3), (-3, -2), (2,3), (3, 2)}

Explanation:

A function is a set of ordered pairs in which no two pairs have the same first number.

In other words, an x cannot be paired with two y's.

A function takes an x and pairs it with one and only one y.

{(0,0), (0, 2), (2.0), (2, 2)} is not a function because it pairs 0 with both 0 and 2.

{(2,-1), (2, 1), (3,-1), (3, 1)} is not a function because it pairs 2 with both -1 and 1.

{(2, 2), (2, 3), (3, 2), (3, 3)} is not a function because it pairs 2 with both 2 and 3.