Question

解方程组y/3-x+1/6=3 2(x-y/2)=3(x+y/18)

Answer 1

y/3-x+1/6=3 ------(1)
2(x-y/2)=3(x+y/18)------(2)
(1) 两边同乘6 2y-6x+1=18 2y-6x=17 ---(3)
(2) 2x-y=3x+y/6 两边同乘6 12x-6y=18x+y
6x+7y=0 ---(4)
(3)+(4) 得 9y=17 y=17/9 代入（4)
x=-119/54

Answer 2

y/3-x+1/6=3 ------(1)
2(x-y/2)=3(x+y/18)------(2)
1) 两边同乘6 2y-x-1=18 x-2y=-19--(3)
(2) 2x-y=3x+y/6 两边同乘6 12x-6y=18x+y
6x+7y=0 ---(4)

(3)+(4)y=114/19把y=114/19代入（1）
x=31