Question

解二元一次方程组：3(x+y)-4(x-y)=4,x+y/2+x-y/6+1

Answer 1

3(x+y)-4(x-y)=4,①

x+y/2+x-y/6=1 ,则3(x+y)+(x-y)=6②

②-①,得5(x-y)=2,解得x-y=2/5③

代入②,得x+y=28/15④

③+④,得2x=34/15,解得x=17/15

代入③,解得y=11/15