根据3(x+y)-2(x-y)=11,4(x+y)+3(x-y)=9可得出x+y= ,x-y=

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根据3(x+y)-2(x-y)=11,4(x+y)+3(x-y)=9可得出x+y= ,x-y=
根据3(x+y)-2(x-y)=11,4(x+y)+3(x-y)=9可得出x+y= ,x-y=

根据3(x+y)-2(x-y)=11,4(x+y)+3(x-y)=9可得出x+y= ,x-y=
(x+y)-2(x-y)=11①
4(x+y)+3(x-y)=9②
②-①×4:11(x-y)=-35
(x-y)=-35/11
代入①:(x+y)-2(-35/11)=11
(x+y)=11-70/11
(x+y)=51/11

x+y=a,x-y=b
3a-2b=11,4a+3b=9
a=3,b=-1
故:x+y=3
x-y=-1

设x+y=n,x-y=m,则得:3n-2m=11,4n+3m=9,根据此方程式可解m=-1,n=3,