已知x+2y-z=8,2x-y+z=18,则8x+y+z= ___ .
已知x+2y-z=8,2x-y+z=18,则8x+y+z= ___ .
已知x+2y-z=8,2x-y+z=18 ,求8X+Y-Z的值
已知x+2y-3z=0,2x+3y+5z=0,则x+y+zx-y+z= ___ .
已知X、Y、Z满足2X-Y+4Z=8(1);X-2Y-Z=7(2)求X-Y-Z的值
已知x,y,z满足2x-y+4z=8,x-2y-z=7,求x-y+z的值.要2种方法
已知:X、Y、Z满足2X-Y+4Z=8,X-2Y-Z=7,求X-Y+Z的值
已知x,y,z满足2x-y+4z=8,x-2y-z=7,求x-y+z的值.
已知4x-3y+z=0,x+2y-8z=0,xyz不等于0,求x+y-z/x-y+2z的值
1 已知想x,y,z满足2x-y+4z=8,x-2y-z=7,求x-y+z的值
已知 x,y,z都是正实数,且 x+y+z=xyz 证明 (y+x)/z+(y+z)/x+(z+x)/y≥2(1/x+1
已知(x+y+z)^2=x^2+y^2+z^2,证明x(y+z)+y(z+x)+z(x+y)=0
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