Find the domain of $LaTeX: \displaystyle f(x) = \sqrt{20 x - 12} + 13$ . 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 $LaTeX: \displaystyle 20 x - 12 \geq 0$ . Isolating $LaTeX: \displaystyle x$ gives $LaTeX: \displaystyle 20 x \geq 12$ Dividing to finish isolating $LaTeX: \displaystyle x$ gives $LaTeX: \displaystyle x \geq \frac{3}{5}$ . The domain is $LaTeX: \displaystyle \left[\frac{3}{5}, \infty\right)$