Question

13£®ÒÔ$\left\{\begin{array}{l}{x=1}\\{y=-1}\end{array}\right.$Ϊ½âµÄ¶þÔªÒ»´Î·½³Ì×éÊÇ£¨¡¡¡¡£©

• A£® $\left\{\begin{array}{l}{x+y=0}\\{x-y=1}\end{array}\right.$
• B£® $\left\{\begin{array}{l}{x+y=0}\\{x-y=-1}\end{array}\right.$
• C£® $\left\{\begin{array}{l}{x+y=0}\\{x-y=-2}\end{array}\right.$
• D£® $\left\{\begin{array}{l}{x+y=0}\\{x-y=2}\end{array}\right.$

Answer 1

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