Question

若|x-2y-1|+|2x-y-5|=0.则x-y=

如上求过程谢谢

Answer 1

因为原式=0，所以x-2y-1=0,2x-y-5=0,解方程组得，x=3,y=1

Answer 2

x-2y-1=0(1)
2x-y-5=0(2)
(1)+(2)
3x-3y-6=0
3(x-y)=6
x-y=2

Answer 3

∵|x-2y-1|+|2x-y-5|=0
∴x-2y-1=0
2x-y-5=0
解得x=3； y=1
∴x-y=2

Answer 4

2或4