x/2=y/3=z/4 3x-5y+3z=18求解

(4x-2y-z)-{5x-[8y-2z-(x-2y)]-x-(3y-10z)}=? (4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuaihuajian 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 x/2=y/3=z/5 x+3y-z/x-3y+z (4x-2y-z)-{5x-[8y-2z-(x+y)]-2(3y-10z)}=?好难啊 x+y/2=z+x/3=y+z/4 x+y+z=27 x+2y=3x+2z=4y+z 求x:y:z 已知(x+y)(x+z)=x,(y+z)(y+x)=2y,(z+x)(z+y)=3z,求x,y,z 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/x+y=y+z/2(y-z)=z+x/3(z-x),求证8x+9y+5z=0THX.. 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：4x-5y+2z=0 x+4y-3z=0则：(x*x+y*y+z*z)/(x*y+y*z+z*x)=____.