|x. (x - 4)| = 10x
=> |x2 - 4x| = 10x
\(\Rightarrow\left[{}\begin{matrix}x^2-4x=10x\\x^2-4x=-10x\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x^2-4x-10x=0\\x^2-4x+10x=0\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x^2-14x=0\\x^2+6x=0\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x\left(x-14\right)=0\\x\left(x+6\right)=0\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x=0\\x-14=0\\x+6=0\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x=0\\x=14\\x=-6\end{matrix}\right.\)
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