若x-y=6,xy=-8,求代数式(x+y+z)²+(x-y-z)(x-y+z)-2·z(x+y)的值
若x-y=6,xy=-8,求代数式(x+y+z)²+(x-y-z)(x-y+z)-2·z(x+y)的值
若xy-z不等于0,且(y+x)/x=(z+x)/y=(y+x)/z,求[(y+z)(z+x)(x+y)]/xyz的值?
x y z x+y--- = --- = ---- ----y+Z z+x x+y ,求 z 的值 .求 x+y----
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
已知:(x+y-z)/z=(x-y+z)/y+(y+z-x)/x,且xyz≠0,求代数式[(x+y)(y+z)(x+z)
若x+y=8,xy+z平方=-16,求x+y+z的值
若xyz不等于0,且满足(y+z)/x=(x+z)/y=(x+y)/z,求(y+z)(x+z)(x+y)/xyz的值
若xyz不等于0,且(y+z)/x=(z+x)/y=(x+y)/z,求(y+z)(z+x)(x+y)/xyz的值?
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
(x+y-z)(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.
已知x,y,z满足x/(y+z)+y/(z+x)+z/(x+y)=1,求代数式x2/(y+z)+y2/(x+z)+z2/