Question

look at this table:
x | y
-20 | 3
-5 | 19
1 | 10
9 | 2
-14 | 0
is this relation a function?
yes no

Explanation:

A relation is a function if every input (x-value) has exactly one unique output (y-value). Checking the table, each x-value (-20, -5, 1, 9, -14) appears only once, so each has one corresponding y-value.

Answer:

yes