How do you find the domain of `f (x) = sqrt (-x + 9)`?

Related questions

• How do you determine if (-1, 4), (2, 8), (-1, 5) is a function?
• What is the domain for `f(x)=2x-4`?
• What is the domain and range for (3,1), (1,-4), and (2, 8)?
• What is the domain and range of a linear function?
• Is domain the independent or dependent variable?
• How do you find the domain and range of a function in interval notation?
• How do you find domain and range of a rational function?
• How do you find domain and range of a quadratic function?
• How do you determine the domain and range of a function?
• What is Domain and Range of a Function?