Question

21. Which relation is a function?

A. (,0), (0, 1), (2, 2)}
B. {(-2,2), (-1, 1), (-2,4)}
C. {(-1,4), (0, 5), (0,4)}
D. {(2, 1), (4,3), (6,5)}

Answer 1

D

Explanation:

A function is a relation where every input has only 1 output.

Inputs are the x's and outputs are the y's.

Answer a is missing an input. You have (,0) The first number is missing.

B is not a function because the input -2 has to outputs 2 and 4.

C is not a function because the input 0 has two outputs 5 and 4

Answer 2

The correct answer is D

Explanation:

In order for a relation to be a function, every input for x can only have one output. Therefore, D is the correct answer.