3(x+y)-4(x-y)=4(x+y)/2+(x-y)/6=1令a=x+y,b=x-y3a-4b=4 (1)a/2+b/6=1则3a+b=6 (2)(2)-(1)5b=2b=2/5a=(6-b)/3=28/15x+y=28/15x-y=2/5相加2x=34/15x=17/15y=28/15-x=11/15
解方程得x=17/43,y=27/43
