x-y-z=0,x+y-7z=0,求x∧2+2y∧2-3z∧2÷x∧2-2y∧2+4z∧2
已知(z-x)∧2-4(x-y)(y-x)=0求x+z-2y+8的值
如果|x+y+z-6|+|2x+3y-z-12|+|2x-y-z|=0求x,y,
已知x+4y+3z=3x-2y-5z=0,求x+2y-z/2x-3y+7z的值
已知有理数x、y、z满足条件|x-z-2|+(3x-6y-7)^2+|3y+3z-4|=0,求x、y、z
已知x、y、z满足方程组:x+y-z=6;y+z-x=2;z+x-y=0 求x、y、z的值
试证明(x+y-2z)+(y+z-2x)+(z+x-2y)=3(x+y-2z)(y+z-2x)(z+x-2y)
已知,方程组:4x-3y-7z=0 x+2y=10z 则(x-y+z)÷(x+y+z)=——
已知x,y,z 大于0,x+y+z=2,求证 xz/y(y+z)+zy/x(x+y)+yx/z(z+x)大于等于2/3
x=y/z=z/3,x+y+z =12,求2x+3y+4z是多少,
x*x+y*y+2z*z-2x+4y+4z+7=0,求xyz的值
若x/2=y/3=z/4不等于0,求x+y+z/x+y-z的值
若4x-3y-6z=0,x+2y-7z=0,求代数式5x*5x+2y*2y-z*z/2x*2x-3y*3y-10z*10