下列运算中，正确的是_刷题宝

题干

下列运算中，正确的是（）

A：4x+3y=7xy

B：3x²+2=5x²

C：6xy-4xy=2xy

D：5x²-x²=4

上一题下一题 0.0难度选择题更新时间:2017-05-26 01:29:32

答案(点此获取答案解析）

C

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