Ta có: \(2x-\left|5x-1\right|=7\)
\(\Leftrightarrow\left|5x-1\right|=2x-7\)
\(\Leftrightarrow\left[{}\begin{matrix}5x-1=2x-7\left(x\ge\dfrac{1}{5}\right)\\5x-1=7-2x\left(x< \dfrac{1}{5}\right)\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}5x-2x=-7+1\\5x+2x=7+1\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}3x=-6\\7x=8\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=-2\left(loại\right)\\x=\dfrac{8}{7}\left(loại\right)\end{matrix}\right.\)
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