Question

Which of the sets of ordered pairs represents a function?

A = {(−4, 5), (1, −1), (2, −2), (2, 3)}

B = {(2, 2), (3, −2), (9, 3), (9, −3)}

1. Only A
2. Only B
3. Both A and B
4. Neither A nor B

Answer 1

A function WILL NOT have any repeating x values. They can have repeating y values, just not the x ones. So just look at the x values.

so look at x values in A.....are there any repeating x values ? Yes there is....there are repeating 2's...therefore, A is not a function.

now look at the x values in B...are there any repeating x values ? yes there is....there are repeating 9's....so B is not a function.

so neither A or B are functions