1: =>x+1=5
=>x=4
2: \(\Leftrightarrow\left|x-5\right|=2x+2\)
\(\Leftrightarrow\left\{{}\begin{matrix}x>=-1\\\left(2x+2-x+5\right)\left(2x+2+x-5\right)=0\end{matrix}\right.\)
\(\Leftrightarrow\left\{{}\begin{matrix}x>=-1\\\left(x+7\right)\left(3x-3\right)=0\end{matrix}\right.\Leftrightarrow x=1\)
3: \(\Leftrightarrow\sqrt{3+x}\left(\sqrt{3-x}+1\right)=0\)
=>x+3=0
=>x=-3