化简-{-[-(5x-4y)]}的结果是( )A.5x-4yB.4y-5xC.5x+4yD.-5x-4y
题型:单选题难度:一般来源:不详
化简-{-[-(5x-4y)]}的结果是( )A.5x-4y | B.4y-5x | C.5x+4y | D.-5x-4y |
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答案
-{-[-(5x-4y)]} =[-(5x-4y)] =-(5x-4y) =-5x+4y =4y-5x 故选B. |
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