Answer:
6 ≤ x ≤ ∞
Explanation:
The domain is the "allowable inputs" or x-values. We know that there cannot be a negative number under a radical, so that means "x-6" must be greater than or equal to zero. Thus, we can set up the equation:
x - 6 ≥ 0
x ≥ 6 This is the domain
There aren't restrictions on positive x-values, so we can also write the domain as:
6 ≤ x ≤ ∞