5x-3y+z=2,5x+2y-4y,-5x+y-z=2三元一次方程组

(4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuaihuajian (4x-2y-z)-{5x-[8y-2z-(x-2y)]-x-(3y-10z)}=? 设|x|-|y|+|z|=|x+y+z|,且|x+y|=4,|y+z|=5,|y|=3,求(x-y-z)^2的值 x+y=5 2x+3y-z=9 x-y+z=4 (4x-2y-z)-{5x-[8y-2z-(x+y)]-2(3y-10z)}=?好难啊 x/2=y/3=z/5 x+3y-z/x-3y+z x:y=3:2 y:z=5:4 x+y+z=66 x:y=3:2 y:z=5:4 x+y+z=66 {x:y=2:3 y:z=4:5 x+y+z=35 x:y=2:3 y:z=4:5 x+y+z=35 x+y+z=111,y:x=3:2,y:z=5:4 3x=4y 2y=5z 试求x:y:z 已知x-y/x+y=y+z/2(y-z)=z+x/3(z-x),求证8x+9y+5z=0THX.. 1.（x+y-z)+(x-y+z)-(x-y-z) 2.2x-(3x-2y+3)-(5y-2) 已知：4x-5y+2z=0 x+4y-3z=0则：(x*x+y*y+z*z)/(x*y+y*z+z*x)=____. ｛ 5x-3y+z=25x+2y-4z=3-5x+y-z=2 x-y+z=-1 5x+2y-z=6 4x-3y+2z=-5 x:y:z=3:4:5 2x-3y+2z=8 x-y-2z=?