$\left\{\begin{matrix}x=-\sqrt{z-10\sqrt{z+10}+35}-5\text{, }&z<90\text{ and }y=z-10\sqrt{z+10}+10\text{ and }z\geq 15\\x=\sqrt{z-10\sqrt{z+10}+35}-5\text{, }&y=z-10\sqrt{z+10}+10\text{ and }z\leq 15\text{ and }z>-10\end{matrix}\right.$

$\left\{\begin{matrix}z=y-10\sqrt{y+25}+40\text{, }&y\geq -25\text{ and }x=-\sqrt{y-10\sqrt{y+25}+50}\text{ and }y<0\\z=\left(\sqrt{y+25}+5\right)^{2}-10\text{, }&y<0\text{ and }x=-\left(\sqrt{y+25}+5\right)\text{ and }y\geq -25\end{matrix}\right.$