题目

与直线x+2y-1=0关于点(1，-1)对称的直线方程为(    )A.2x-y-5=0          B.x+2y-3=0               C.x+2y+3=0        D.2x-y-1=0 答案：解析：将x+2y-1=0中的x、y分别代以2-x,-2-y,得(2-x)+2(-2-y)-1=0,即x+2y+3=0.故选C.答案：C

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