Which of the following sets of ordered pairs in the form (x,y) represent a function of x?

3 points



{(2,4), (-2,4), (5,3), (7,4)}



{(3,5),(-1,1),(3,2), (-6,2)}



{(9,2), (-3,4), (-3,1), (7,-4)}



{(5,1),(-2,-1),(5,-4), (6,1)

Show work please