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

3x+3y-4x+4y=4

x-7y=-4 (1)

x+y/2+x-y/6=1

3x+3y+x-y=6

2x+y=3 (2)

(1)+(2)×7

15x=17

所以x=17/15

y=3-2x=11/15