Answer
$ 4\sqrt{x+2}$
Work Step by Step
Given\begin{equation}
\sqrt{x+2}+3 \sqrt{x+2}.
\end{equation} Add the radical expressions because the radicand are the same.
\begin{equation}
\begin{aligned}
\sqrt{x+2}+3 \sqrt{x+2}& =\left( 1+3 \right)\sqrt{x+2} \\
& =4\sqrt{x+2}.
\end{aligned}
\end{equation}
