解下列方程 8x+9y=17 x-3y=-2

2024-11-24 04:56:28
推荐回答(2个)
回答1:

8x + 9y = 17,
x - 3y = -2,
这个方程组,
x - 3y = -2,
3x - 9y = -6,
3x - 9y + 8x + 9y = -6 + 17,
11x = 11,
x = 1,
x - 3y = -2,
1 - 3y = -2,
3 - 3y = 0,
1 - y = 0,
y = 1,
解方程组,
x = 1,
y = 1,

回答2:

由x-3y=-2得:x=3y-2
将x=3y-2带入8x+9y=17得y=1