Question

{x+3y=5 ,3x-6y=6

Answer 1

x+3y=5①

3x-6y=6②

由①得：x=5-3y代入②

3（5-3y)-6y=6

15-9y-6y=6

-15y=-9

y=3/5

∴x=5-3×3/5=16/5

即：方程组的解为：x=16/5；y=3/5