问题
填空题
若|x-y+3|+
|
答案
∵|x-y+3|+
=0,x+y-5
∴可得|x-y+3|=0且
=0,x+y-5
∴可求得:
,x-y=-3 x+y=5
∴有
,x=1 y=4
∴
-(x-y)x+2y x-y
=
-(-3)x+y+y -3
=
+35+4 -3
=0,
故答案为0.
若|x-y+3|+
|
∵|x-y+3|+
=0,x+y-5
∴可得|x-y+3|=0且
=0,x+y-5
∴可求得:
,x-y=-3 x+y=5
∴有
,x=1 y=4
∴
-(x-y)x+2y x-y
=
-(-3)x+y+y -3
=
+35+4 -3
=0,
故答案为0.