Question

Which of the following represents a relation that is not a function?
A.x,y
-10,25
-4,23
-1,31
4,25
B.x,y
7,25
-4,23
12,31
4,25
C.x,y
-10,25
-4,23
-10,31
12,25
D.x,y
-10,25
-4,23
-10,31
4,25

Answer 1

Neither C nor D are functions. A function can be defined as a set of coordinates in which there is only one y-value for every x-value, and for both of those, there are two different y-values for -10.