Question

Which of the following pairs could represent a function? Select three that apply.

A: {(2,-5),(4,-5), (6,2), (8,3)}**
B: {(-1,5),(3,5),(6,5), (9,5)}**
C: {(3,-4),(5,2), (3,8), (6,7)}
D: {(0,3), (4,2),(-1,7), (0,3)}
E: {(-1,1),(-1,6),(-1,8), (-1,0)}
F: {(-4, 2),(3,-2), (-4,-2), (5,1)}

We are supposed to select three that are correct, but I've only figured out 2 so far. Can anyone help me figure out the third one? Thanks in advance.

Answer 1

as long as each x value appears only once, it is probably a function. So, I'd pick A and B on that basis.

D also works. While 0 appears twice as the first element, the 2nd element is the same. So, the pair (0,3) appears twice, but it does not violate the rules for functions.

Answer 2

^^ simple version of what steve said:

even tho the x-value "0" appears twice, it doesn't count because it has the same y-value, so they overlap each other.
so if you were to graph it, you would only see 3 points, even tho there are really 4.

Answer 3

Ans: A, B, and D. I just did it. Thank you steve and Honors student. They have correct and. with the correct explanation.