Question

look at this set of ordered pairs:
(9, 8)
(13, -4)
(0, 18)
(-20, 19)
(-6, 2)
(16, 12)
is this relation a function?
yes
no

Explanation:

Step1: Identify all input values

Input values (x-coordinates): $9, 13, 0, -20, -6, 16$

Step2: Check for repeated inputs

No input value appears more than once.

Step3: Apply function definition

A relation is a function if each input has exactly one output.

Answer:

yes