x+y+z=2 ① 2x+3y+z=38 ① x+y=3 3x-y-4z=5 ② 3x+4y+2z+56 ② y+z=5

x+y+z=2 ① 2x+3y+z=38 ① x+y=3 3x-y-4z=5 ② 3x+4y+2z+56 ② y+z=5 x/2=y/3=z/5 x+3y-z/x-3y+z 试证明(x+y-2z)+(y+z-2x)+(z+x-2y)=3(x+y-2z)(y+z-2x)(z+x-2y) ①x+y+z=6 3x-y+2z=12 x-y-3z=-4 ②x+y-z=2 4x-2y+3y+8=0 x+3y-2z- 三元一次方程求解：①x+2z=3,2x+y=2,2y+z=7.②x+y+z=2,3x-y-4z=5,2x+3y-2z=0 2x+3y+z=38 ① 3x+4y+2z=56 ② 4x+5y+z=66 ③ (4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuai x=y/z=z/3,x+y+z ＝12,求2x+3y+4z是多少, 解三元一次方程组：（一）2x+y+z=4① x-y+3z=3 ②x+z=2③ 二；①2x+y+z=2 ②x+2y+z=5 1.解下列方程组,①y-2z=1,x+3z=-1,3x-5y+z=21.②x+y+2z=7,x-2y-z=-4,2x+3 已知3x-2y-5z=0,2x-5y+4z=0,且x,y,z均不为0,求3x*x+2y*y+5z*z/5x*x+y*y- {2x+3y-4z=-5 x+y+z=6 x-y+3z=10