\(\hept{\begin{cases}mx-2y=-1\\2x+3y=1\end{cases}}\Leftrightarrow\hept{\begin{cases}2x=1-3y\\mx-2y=-1\end{cases}}\)
\(\Leftrightarrow\hept{\begin{cases}x=\frac{1-3y}{2}\\\frac{m-3my}{2}-\frac{4y}{2}=-1\end{cases}}\Leftrightarrow\hept{\begin{cases}x=\frac{1-3y}{2}\\m-3my-4y=-2\end{cases}}\)
\(\Leftrightarrow\hept{\begin{cases}x=\frac{1-3y}{2}\\m-y\left(3m+4\right)=-2\end{cases}}\Leftrightarrow\hept{\begin{cases}x=\frac{1-3y}{2}\\y\left(3m+4\right)=m+2\end{cases}}\)
\(\Leftrightarrow\hept{\begin{cases}x=\frac{1-3y}{2}\\y=\frac{m+2}{3m+4}\end{cases}}\)
vậy....