Question

Which set is a function?

A {(6,2), (2,0), (4,6), (6,4)}
B {(0,2), (2,0), (4,6), (6,4)}
C {(2,6), (3,6), (4,6), (2,0)}
D {(0,4), (0,9), (12,6), (-3,9)}
E {(0,3), (3,0), (0,4), (4,0)}

Answer 1

Explanation:

B is a function because each x-value has a unique y-value.

All other sets have an x-value which has 2 different y-values. These cannot be functions.