Answer:
The domain is the set of numbers that the x value can be.
In an equation like the domain is all real numbers because x can be any number.
In the case of , any x value that is less than or equal to -4 will not work because you would be taking the square root of a negative number, which doesn't work unless you're graphing on a complex plane, which I assume you aren't.
Thus, the domain is
I hope that helps!
Explanation: