Question

Which of the following relations is not a function?

{(0, 0), (1, 0), (2, 0)}
{(-1,3), (4,2), (-1,5)}
{(1, 2), (3, -5), (-1, 7)}
{[7, -1), (3,-2), (5,-2)}

Answer 1

{(-1,3), (4,2), (-1,5)}

Explanation:

Answer 2

{(-1,3), (4,2), (-1,5)}

The same inputs should have the same output, but different inputs are allowed to have the same output.
I hope this helped!