Đáp án:
Giải thích các bước giải:
\(\begin{array}{l}
c.\left\{ \begin{array}{l}
\left( {x - 3} \right)\left( {2y + 5} \right) = \left( {2x + 7} \right)\left( {y - 1} \right)\\
\left( {4x + 1} \right)\left( {3y - 6} \right) = \left( {6x--1} \right)\left( {2y + 3} \right)
\end{array} \right.\\
\to \left\{ \begin{array}{l}
2xy + 5x - 6y - 15 = 2xy - 2x + 7y - 7\\
12xy - 24x + 3y - 6 = 12xy + 18x - 2y - 3
\end{array} \right.\\
\to \left\{ \begin{array}{l}
7x - 13y = 8\\
42x - 5 = - 3
\end{array} \right.\\
\to \left\{ \begin{array}{l}
42x - 78y = 48\\
42x - 5 = - 3
\end{array} \right. \to \left\{ \begin{array}{l}
73y = - 51\\
42x - 5 = - 3
\end{array} \right.\\
\to \left\{ \begin{array}{l}
y = - \frac{{51}}{{73}}\\
x = - \frac{{79}}{{511}}
\end{array} \right.\\
d.\left\{ \begin{array}{l}
\frac{3}{2}x - y = \frac{1}{2}\\
3x - 2y = 1
\end{array} \right.\\
\to \left\{ \begin{array}{l}
3x - 2y = 1\\
3x - 2y = 1
\end{array} \right.
\end{array}\)
⇒ Hệ pt có vô số nghiệm
