解:去括号,得x+1﹣2x﹣1=1﹣3x.①
移项,得x﹣2x+3x=1+1﹣1.②
合并同类项,得2x=1.③
系数化为1,得x= 12 .④
上述解答过程错在哪一步?指出并加以更正.
正确解法为:去括号,得x+1﹣2x+2=1﹣3x.
移项,得x﹣2x+3x=1﹣2﹣1.
合并同类项,得2x=﹣2.
系数化为1,得x=﹣1.
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