Find the domain of LaTeX:  \displaystyle f(x) = \sqrt{5 x + 10} + 9 . Write the solution in interval notation.

The domain of a radical function is the solution to the inequality radicand LaTeX:  \displaystyle \geq 0 . The inequality is LaTeX:  \displaystyle 5 x + 10 \geq 0 . Isolating LaTeX:  \displaystyle x gives LaTeX:  \displaystyle 5 x \geq -10 Dividing to finish isolating LaTeX:  \displaystyle x gives LaTeX:  \displaystyle x \geq -2 . The domain is LaTeX:  \displaystyle \left[-2, \infty\right)