若实数x,y满足(x+y)(x+y-3)+2=0,则x+y的值为( )A.-1或-2B.-1或2C.1或-2D.1或2
题型:单选题难度:简单来源:不详
若实数x,y满足(x+y)(x+y-3)+2=0,则x+y的值为( ) |
答案
(x+y)(x+y-3)+2=0, (x+y)2-3(x+y)+2=0, (x+y-2)(x+y-1)=0, x+y-2=0,x+y-1=0, x+y=2,x+y=1, 故选D. |
举一反三
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