You can put this solution on YOUR website! We have f(x) = 10 - sqrt[3 - x].
Set what lies in the radicand to be greater than or equal to zero and then solve for x.
3 - x ≥ 0
-x ≥ -3
Since we are dividing by a negative number, the inequality sign must by reversed.
x ≤ -3/-1
x ≤ 3
This makes sense because any number bigger than 3 that we replace x with in the radicand will make your square root undefined.
The domain is: ALL REAL NUMBERS EXCEPT THAT X MUST BE LESS THAN OR EQUAL TO 3.