\(\left|x+1\right|-9=-7\)
\(\Rightarrow\left[{}\begin{matrix}x+1=2\\x+1=-2\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=2-1\\x=\left(-2\right)-1\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=1\\x=-3\end{matrix}\right.\)
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