i understand the concept of domain and range

Question

domain--set of all possible inputs for the function
range-set of all possible outputs

but I don't know how to find

example:
state the domain and range of
f(x)=10-√(3-x)

thank you

Answer 1

The domain of √x is x≥0
so, the domain of ≥(3-x) is
3-x ≥ 0
x ≤ 3
since y is decreasing, and y(3) = 10, the range is y≤ 10