Question

Which of the following relations is a function?
A.
(8, 1), (-2, 4), (2, 1), (8, 2)

B.
(2, 4), (-2, 6), (2, 3), (-8, 2)

C.
(2, 4), (-2, 2), (8, 1), (-8, 2)

D.
(2, 0), (-2, 3), (8, 1), (-2, 5)

Answer 1

in a function, no x value repeates

Answer 2

in A x value repeats
in B x value also repeats
in C x value doesn't repeats
In D x value repeats

Answer 3

thus C is the function

Answer 4

a relation is a function when there is only one output for a given input

there is only one y-value for a given x-value