Given:
The set of ordered pairs in the options:
(a) (2, 3), (2, 2), (2, 4), (2, 9), (2, –2)
(b) (1, 5), (2, 6), (1, 6), (4, 5), (1, 4)
(c) (1, 0), (2, 0), (1, 3), (4, 3), (5, 7)
(d) (5, 1), (7, 3), (9, 5), (11, 7), (13, 9)
To find:
The set of ordered pairs that could represent a function.
Solution:
A set of ordered pairs represent a function, if there exist unique output (y-value) for each input (x-value).
In option (a) we have, five output values y=3,2,4,9,-2 for single input x=2. So, it is not a function.
In option (b) we have, three output values y=5,6,4 for single input x=1. So, it is not a function.
In option (c) we have, two output values y=0,3 for single input x=1. So, it is not a function.
In option (d), all inputs has unique output.
Therefore, the correct option is (d).
= 
=