Question

Which of the following tables does not represent a function?

x y
-1 1
-2 1
-3 1

x y
-5 1
-5 -2
-5 -5

x y
-4 0
2 0
5 7

x y
-5 1
-3 -2
-1 -5

Answer 1

Explanation:

the second one (with the -5 as x values) is not a function, because the valid x value -5 has more than one associated different solution value y.

for a function a valid x value can lead only to exactly one result y value.