解三元一次方程组:x+y-z=0 ① 3x+y=6 ① 2x-y+3z=2 ② x+2y-z=5 ② x-4y-2z+6=0 ③ 5x-3y+2z=4 ③

问题描述:

解三元一次方程组:x+y-z=0 ① 3x+y=6 ① 2x-y+3z=2 ② x+2y-z=5 ② x-4y-2z+6=0 ③ 5x-3y+2z=4 ③
x+y+z=-1 ① 2x+3y=5 ①
4x-2y+3z=5 ② 3y-4z=3 ②
y-z=8-2x ③ 4z+5x=7 ③

(1)题的过程:由x+y-z=0可得z=x+y,代入剩余两个方程可得:2x-y+3(x+y)=2,x-4y-2(x+y)+6=0,整理得:5x+2y=2,x+6y=6(这个式子可以两边同乘5得:5x+30y=30),由5x+2y=2,5x+30y=30两式相减消去5x,可得28y=28,y=1,再由x...