解方程组 3x+4z=7 2x+3y+z=9 5x-9y+7z=8

解方程组：2x+3y+4z=20,x+y+z=7 解方程组解方程组｛y=2x-7｛x+y+z=1｛3x-z=4 解方程组：3x+7y+z=31.5,4x+10y+z=42求 x+y+z 解方程组：2x+y+z=-4 x+2y+z=-2 x+y+2z=3 解方程组{3x+y-z=4,2x-y+3z=12,x+y+z=6} 解方程组2x+3y-z=12,3x-y+z=4,x+y+z=6 解方程组x+y-z=0,2x+y+z=7,x-3y+z=8 解方程组 x+y+z=5 2x-y-z=4 3x-2y-z=9 解方程组x+y+z=6 x+2y-3z=4 2x-y+z=5 解方程组x+y/2=z+x/3=y+z/4①x+y+z=27② 解方程组x-4y+z=-3,2x+y-z=18,x-y-z=7. 解方程组：x+y+z=4,x+y+2z=5,3x+y-z=6 x+y+z+2,4x+2y+z+2,9x+3y+z=6解方程组 三元一次方程组5x-4y+4z=132x+7y-3z=193x+2y-z=18解这个方程组 解三元一次方程组 ①2x-y+z=1 3x+y -2z=2 X+2y-z=3 ②x-4y+z=-3 2x+Y-Z=18 X-Y-Z=7 ③4x+4y+2z=7 6X-4y-z=6 2x-y+z=1 { x+y+z=7 x+2y=4 z=3x-2y 解方程组 解方程组｛2x+5y+z=3 3z-2y-z=-7 4x+2y-z=-14 解方程组:x+2y+3z=80,x/2+y/3=z/4,