g) \(|9-7x|=5x-3\)Vì \(|9-7x|\ge0\)\(\Rightarrow5x-3\ge0\)\(\Rightarrow5x\ge3\)\(\Rightarrow x\ge\frac{3}{5}\)Ta có: \(|9-7x|=5x-3\)\(\Leftrightarrow\orbr{\begin{cases}9-7x=5x-3\\7-7x=3-5x\end{cases}}\)\(\Leftrightarrow\orbr{\begin{cases}-7x-5x=-3-9\\-7x+5x=3-7\end{cases}}\)\(\Leftrightarrow\orbr{\begin{cases}-12x=-12\\-2x=-4\end{cases}}\)\(\Leftrightarrow\orbr{\begin{cases}x=1\left(chon\right)\\x=2\left(chon\right)\end{cases}}\)\(\Rightarrow...
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g) \(|9-7x|=5x-3\)
Vì \(|9-7x|\ge0\)
\(\Rightarrow5x-3\ge0\)
\(\Rightarrow5x\ge3\)
\(\Rightarrow x\ge\frac{3}{5}\)
Ta có: \(|9-7x|=5x-3\)
\(\Leftrightarrow\orbr{\begin{cases}9-7x=5x-3\\7-7x=3-5x\end{cases}}\)
\(\Leftrightarrow\orbr{\begin{cases}-7x-5x=-3-9\\-7x+5x=3-7\end{cases}}\)
\(\Leftrightarrow\orbr{\begin{cases}-12x=-12\\-2x=-4\end{cases}}\)
\(\Leftrightarrow\orbr{\begin{cases}x=1\left(chon\right)\\x=2\left(chon\right)\end{cases}}\)
\(\Rightarrow x\in\left\{1;2\right\}\)
h) \(8x-|4x+1|=x+2\)
\(\Rightarrow|4x+1|=7x+2\)
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