Question

9£®ÏÂÁз½³Ì×éÖУ¬ÄÄÏîµÄ½âÊÇ$\left\{\begin{array}{l}{x=-1}\\{y=-2}\end{array}\right.$£¨¡¡¡¡£©

• A£® $\left\{\begin{array}{l}{x+y=1}\\{x-y=2}\end{array}\right.$
• B£® $\left\{\begin{array}{l}{x+y=1}\\{x-2y=3}\end{array}\right.$
• C£® $\left\{\begin{array}{l}{2x=y}\\{y+x=-3}\end{array}\right.$
• D£® $\left\{\begin{array}{l}{\frac{x}{2}-\frac{y}{6}=1}\\{x+y=3}\end{array}\right.$

Answer 1

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