将2(x+y)-3(x-y)-4(x+y)+5(x-y)-3(x-y)合并同类项得( )A.-3x-yB.-2(x+y)C.-x+yD.-2(x+y)-(x-
题型:单选题难度:简单来源:不详
将2(x+y)-3(x-y)-4(x+y)+5(x-y)-3(x-y)合并同类项得( )A.-3x-y | B.-2(x+y) | C.-x+y | D.-2(x+y)-(x-y) |
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答案
原式=2(x+y)-4(x+y)-3(x-y)+5(x-y)-3(x-y) =-2(x+y)-(x-y) =-2x-2y-x+y =-3x-y, 故选A. |
举一反三
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