\(\sqrt{x+2}+\sqrt{9x+18}=8\left(dkxd:x\ge-2\right)\)
\(\Leftrightarrow\sqrt{x+2}+\sqrt{9\left(x+2\right)}=8\)
\(\Leftrightarrow\sqrt{x+2}+3\sqrt{x+2}=8\)
\(\Leftrightarrow4\sqrt{x+2}=8\)
\(\Leftrightarrow\sqrt{x+2}=2\)
\(\Leftrightarrow x+2=4\)
\(\Leftrightarrow x=2\left(tmdk\right)\)