x+y/3+x-y/2=6 4(x+y)-2(x-y)=40

问题描述:

x+y/3+x-y/2=6 4(x+y)-2(x-y)=40

答:
(x+y)/3+(x-y)/2=6
4(x+y)-2(x-y)=40
整理得:
2(x+y)+3(x-y)=36
2(x+y)-(x-y)=20
两式相减得:
4(x-y)=16
x-y=4
代入得:2(x+y)-4=20
x+y=12
结合x-y=4解得:
x=8,y=4