If xy=x+y and y> 2,which of the following must be true about A.x=yB.x=0C.x=1D.0

分类: 作业答案 • 2022-01-02 12:38:28

问题描述：

If xy=x+y and y> 2,which of the following must be true about
A.x=y
B.x=0
C.x=1
D.0

答

xy-x-y+1=1,即（x-1)(y-1)=1,选E