\(\Leftrightarrow\left\{{}\begin{matrix}4x+2y=2m\\3x-2y=5\end{matrix}\right.\) \(\Rightarrow\left\{{}\begin{matrix}7x=2m+5\\y=m-2x\end{matrix}\right.\)
\(\Rightarrow\left\{{}\begin{matrix}x=\frac{2m+5}{7}\\y=\frac{3m-10}{7}\end{matrix}\right.\)
Để \(\left\{{}\begin{matrix}x>0\\y< 0\end{matrix}\right.\) \(\Rightarrow\left\{{}\begin{matrix}2m+5>0\\3m-10< 0\end{matrix}\right.\) \(\Rightarrow-\frac{5}{2}< m< \frac{10}{3}\)