Question

How do you find the domain of `y = 3/ (x + 6)`?

Answer 1

The domain of your function is the set of `x` values that it can accept as input.
For this function all the Real are allowed except the `x` that makes the denominatori equal to zero (you cannot divide by zero).
So must be `x!=-6`.
Your domain will be all Reals except `-6`.