What is the domain of the function f(x) = x+ 2?

 Choice D)

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Explanation:

Taking the square root of a negative number leads to a nonreal result.

So we want the radicand to be 0 or positive

Set the stuff under the square root to be 0 or larger. Solve for x.

If x is -6 or larger, then is 0 or larger leading to some real number for f(x).

The inequality sign does not flip because we multiplied both sides by a positive number. The inequality sign only flips when we multiply both sides by a negative number.