\[y = \sqrt{x + 4} + \sqrt{2x + 3}\]
\[\left\{ \begin{matrix}
x + 4 \geq 0\ \ \\
2x + 3 \geq 0 \\
\end{matrix} \right.\ \]
\[\left\{ \begin{matrix}
x \geq - 4\ \ \\
2x \geq - 3 \\
\end{matrix} \right.\ \]
\[\left\{ \begin{matrix}
x \geq - 4\ \ \ \\
x \geq - 1,5 \\
\end{matrix} \right.\ \]
\[x \geq - 1,5.\]