Answer:
<em>c</em> can be anything but [2, 12, -1, 0]
If it were any of those numbers, you would have repeating values.
Step-by-step explanation:
A function is a special kind of relation between two variables. Each input corresponds to exactly one output.
In this given relation, we need only one output and correspond to each input.
To fulfill the condition to beome a function, we can take any value for c which belongs to the set of real numbers other than the values which the relation already has taken as input.
<em>c ≠ </em>2, 12, -1. 0
<em><u>Hope this helps!</u></em>
<em><u>Please mark brainliest!</u></em>