The domain is the set of values of x that satisfy the function while the range is the set of values of y that satisfy the function.
To find the domain, we would make the terms inside the square root greater than or equal to 0 and solve for x. thus, we have
3x - 12 ≥ 0
3x ≥ 12
x ≥ 12/3
x ≥ 4
Numbers less than 4 would give us a negative
The domain would include all numbers greater than 4
All vaues of x less than or equal to