\(\left\{{}\begin{matrix}3x+4y=12\\mx+2y=6\end{matrix}\right.\)
ĐKXĐ : \(\left(x\in R>0\right)\)
\(\rightarrow\left\{{}\begin{matrix}3x+4y=12\\2mx+4y=-12\end{matrix}\right.\)
\(\rightarrow\left\{{}\begin{matrix}m=0\\ms+2y=6\end{matrix}\right.\)
\(\rightarrow\left\{{}\begin{matrix}m=0\\2y=6\end{matrix}\right.\)
\(\rightarrow\left\{{}\begin{matrix}m=0\\y=3\end{matrix}\right.\)
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