Answer
$\left\{-\dfrac{9}{4},-2,0,0.6,6,\dfrac{30}{3}\right\}$
Work Step by Step
The expression $0.6$ from the given set, $
\left\{-\dfrac{9}{4},-2,-\sqrt{2},0,0.6,\sqrt{11},\sqrt{-8},6,\dfrac{30}{3}\right\}
$ is equivalent to $\dfrac{6}{10}$. The number $-2$ is equivalent to $\dfrac{-2}{1}$. The number $0$ is the same as $\dfrac{0}{1}$, and the number $6$ is the same as $\dfrac{6}{1}$.
Since rational numbers numbers are numbers that can be expressed as the ratio of two integers, then the rational numbers in the given set are
\begin{align*}
\left\{-\dfrac{9}{4},-2,0,0.6,6,\dfrac{30}{3}\right\}
.\end{align*}
