Đáp án:
$\begin{array}{l}
g)\left\{ \begin{array}{l}
\left( {x + 5} \right)\left( {y - 2} \right) = \left( {x + 2} \right)\left( {y - 1} \right)\\
\left( {x - 4} \right)\left( {y + 7} \right) = \left( {x - 3} \right)\left( {y + 4} \right)
\end{array} \right.\\
\Leftrightarrow \left\{ \begin{array}{l}
xy - 2x + 5y - 10 = xy - x + 2y - 1\\
xy + 7x - 4y - 28 = xy + 4x - 3y - 12
\end{array} \right.\\
\Leftrightarrow \left\{ \begin{array}{l}
x - 3y = - 9\\
3x - y = 16
\end{array} \right.\\
\Leftrightarrow \left\{ \begin{array}{l}
3x - 9y = - 27\\
3x - y = 16
\end{array} \right.\\
\Leftrightarrow \left\{ \begin{array}{l}
8y = 43\\
x = 3y - 9
\end{array} \right.\\
\Leftrightarrow \left\{ \begin{array}{l}
y = \dfrac{{43}}{8}\\
x = 3.\dfrac{{43}}{8} - 9 = \dfrac{{57}}{8}
\end{array} \right.\\
Vậy\,x = \dfrac{{57}}{8};y = \dfrac{{43}}{8}\\
l)\left\{ \begin{array}{l}
x - y = 1\\
3x + 2y = 3
\end{array} \right.\\
\Leftrightarrow \left\{ \begin{array}{l}
2x - 2y = 2\\
3x + 2y = 3
\end{array} \right.\\
\Leftrightarrow \left\{ \begin{array}{l}
5x = 5\\
y = x - 1
\end{array} \right.\\
\Leftrightarrow \left\{ \begin{array}{l}
x = 1\\
y = 0
\end{array} \right.\\
Vậy\,x = 1;y = 0\\
q)\left\{ \begin{array}{l}
x - \dfrac{y}{2} = 5\\
2x - y = 6
\end{array} \right.\\
\Leftrightarrow \left\{ \begin{array}{l}
2x - y = 10\\
2x - y = 6
\end{array} \right.\\
\Leftrightarrow \left\{ \begin{array}{l}
0 = 4\left( {ktm} \right)\\
2x - y = 6
\end{array} \right.
\end{array}$
Vậy hệ pt vô nghiệm
