Question

Which of the following relations is a function?
A 1,2 1,3 1,4 1,5
B 1,3 2,3 4,3 9,3
C 5,4 -6,4 4,5 4,0
D 6,-1 1,4 2,3 6,-1

Answer 1

The function cannot have any domain nor range have any duplications.

Answer 2

Your x values can not repeat, but your y values can in order to have a function.

Answer 3

They're pairs or points or something.

Answer 4

So in A:

(1,2)(1,3)(1,4)(1,5) This is NOT a function because the x value (aka 1) is going to more than 1 y value.

Answer 5

So let's look at B: (1,3)(2,3)(4,3)(9,3)

This IS a function because each x value only goes to 1 y. No x value is repeated.

Answer 6

In C:

(5,4)(-6,4)(4,5)(4,0) This is NOT a function because the x value of 4 is repeated.

Answer 7

In D:

(6,-1)(1,4)(2,3)(6,-1) Not a function because the x value 6 is repeated.

So we know that B is the only function because it is the only one with set of ordered pairs that the x value is not repeated.

Answer 8

So if the x value repeats it won't work, okay thanks a lot marissa

Answer 9

Exactly. Your x value CANNOT repeat but the y values can.

You're welcome :)