Answer:
Yes, set K is a function.
Explanation:
Given K = x - y = 5
we have to find is above set is a function or not.
Functions are relations that give one output for each input, or one x- value gives only one value of y.
As, x-y=5
⇒ y=x-5
The above set is a function because every x-value produces a different y-value i.e K satisfies the definition of what it meant for a relation to be function.
Hence, set K is a function.