which set of ordered pairs does not represent a function?
(4,1), (6,2), (7,5), (9,2)
(0,5), (1,7), (2,9), (3,11)
(-2,5), (0,2), (9,-6), (8,7)
(5,5), (6,10), (10,15), (5,20)
Remember that
A relation between x and y represent a function if for one value of x there is only one value of y
so
Verify each set of ordered pairs
N 1) ------> represent a function
N 2) ----> represent a function
N 3) ----> represent a function
N 4) ----> Not represent a function, because for x=5, y=5 and y=20
therefore
the set (5,5), (6,10), (10,15), (5,20) not represent a function