{x=4y,x+y+z=12,x+2y+5z=22的过程

{x+y+z=12 x+2y+5z=22 x=4y (x+y-z)(x-y+z)= x+y/2=z+x/3=y+z/4 x+y+z=27 x+2y=3x+2z=4y+z 求x:y:z x=y/z=z/3,x+y+z ＝12,求2x+3y+4z是多少, 若x,y,z成等差数列,则(z-x)^2-4(x-y)(y-z)= (x*x+2)(y*y+4)(z*z+8)=64xyz,求x,y,z 若x,y,z成等差数列,则(z-x)^2-4(x-y)(y-x)= 用行列式的性质证明：y+z z+x x+y x y z x+y y+z z+x =2 z x y z+x x+y y+z y z x 这个怎么证? (4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuaihuajian 如果|x+y+z-6|+|2x+3y-z-12|+|2x-y-z|=0求x,y, (4x-2y-z)-{5x-[8y-2z-(x-2y)]-x-(3y-10z)}=? x+y+z=12 x-y+z=2 x-z+y+a=90 x+y+a+z=100,求x y z a 已知x+y/2=y+z/2=x+z/4,且x+2y+z=12,求x-2y+z的值（x+y）/2=（y+z）/2=（x+z/）4 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^2/(z+y)+y^2/(x+z)+z^2/(x+y)=0,求x/(z+y)+y/(x+z)+z/(x+y)的值. x^2/(z+y)+y^2/(x+z)+z^2/(x+y)=0,求x/(z+y)+y/(x+z)+z/(x+y)的值