Question

look at this table:

x	y
4	-1
13	13
6	20
2	12

is this relation a function?
yes no

Explanation:

Step1: Recall the definition of a function

A relation is a function if each input (x - value) has exactly one output (y - value). In other words, no two different ordered pairs have the same x - value with different y - values.

Step2: Check the x - values in the table

We look at the x - values: 16, 4, 13, 6, 2. Each of these x - values appears only once. That means for each x - value, there is only one corresponding y - value.

Answer:

yes