\(\left|x-7\right|+2x+5=6\)
th1: \(x-7\ge0\Leftrightarrow x\ge7\)
\(\Rightarrow\left|x-7\right|+2x+5=6\Leftrightarrow x-7+2x+5=6\)
\(\Leftrightarrow x+2x=6-5+7\Leftrightarrow3x=8\Leftrightarrow x=\dfrac{8}{3}\left(loại\right)\)
th2: \(x-7< 0\Leftrightarrow x< 7\)
\(\Rightarrow\left|x-7\right|+2x+5=6\Leftrightarrow7-x+2x+5=6\)
\(\Leftrightarrow-x+2x=6-5-7\Leftrightarrow x=-6\left(tmđk\right)\)
vậy \(x=-6\)
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