Question

PLS HELP 50 points!!!! Which relation is a function?

O {(-2, 1), (-7, - 1), (2, 8), (-7, – 8)}
O {(-2, 2), (-7, 7), (-1, 1), (-8, 8)}
O {(-2, 1), (-2, 2), (-2, 7), (-2, 8)}
O {(1, -7), (2, – 8), (-2, 7), (1, 8)}

Answer 1

B

Explanation:

For a relation to be a function, it must fit the following criteria:

• Each input must be matched to exactly one output.
• Inputs cannot repeat*. Outputs can.
• *If inputs do repeat, they must be equal the same output as the other inputs.

So, let’s go through each of the choices.

Choice A)

In this relation, -7 repeats. It simultaneously equals -1 and -8. So, this is not a function since it’s repeating and it doesn’t equal to same.

Choice B)

In this relation, none of the inputs are repeating. Therefore, B is the corrrect answer.

Choice C)

In this relation, -2 repeats four times. And each time, it equals something different. Therefore, C is not a function.

Choice D)

Here, 1 repeats twice, equalling both -7 and 8. Since it appeared more than once and is not equal to the same thing, D is not a function.

Therefore, our answer is B.

Edit: Typo