Question

Which of the following sets of ordered pairs does not represent a function?
{(6, 1),(8, 4)(5, 3), (7, 4)}
{(3, 2),(8, 1)(5, 3), (7, 4)}
{(3, 4),(2, 1)(3, 3), (7, 4)}
{(4, 2),(8, 1)(5, 3), (7, 4)}

Answer 1

the ones were the first numbers in the coordinate pairs repeat

Answer 2

{(3, 4),(2, 1)(3, 3), (7, 4)}