4X-5Y+2Z=1,8X-3Y-Z=15,5X+2Y-3Z=18
{x+y+z=1;x+3y+7z=-1;z+5y+8z=-2
x/2=y/3=z/5 x+3y-z/x-3y+z
(4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuai
4x-5z=17 3x+y+15z=18 x+2y+3z=2
x-y-z=-1 3x+5y+7z=11 4x-y+2z=-1 分别求出x=?y=?z=?
已知x::y:z=3:4:5,(1)求x+y分之z的值;(2)若x+y+z=6,求x,y,z.
(1) 4x-9z=17 3x+y+15z=18 x+2y+3z=2 (2)2x+4y+3z=9 3x-2y+5z=11
{5x-3y+z=2{5x+2y-4z=3{-5x+y-z=2 {x-y-z=-1{3x+5y+7z{4x-y+2x=-
试证明(x+y-2z)+(y+z-2x)+(z+x-2y)=3(x+y-2z)(y+z-2x)(z+x-2y)
已知x:y:z=4:5:7,求:(1)2x+3y+z/5z; (2)x+y/y+z.
(1)3x+4z=7;2x+3y+z=9;5x-9y+7z=8 (2)3x+4y+z=14;x+5y+2z=17;2x+
3x+2y+z=14 ,x+y+z=10,z+2x+3y=1 5