已知x-y-z=2,x*x=y*y+z*z=2*y*z=200 求x+y+z=?x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--- = --- = ---- ----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=2,x+y+z=-2.8,求x^2(-y-z)-3.2x(z+y)的值 (x+y-z)(x-y+z)= 已知x+y-z/z=x-y+z/y=-x+y+z/x,且xyz不等于0,求分式[(x+y)(x+z)(y+z)]/xyz 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) 已知2x=3y=4z求2x-y+z分之x+y+z的值 已知x+2y-z=8,2x-y+z=18 ,求8X+Y-Z的值 已知x:y:z=2:3:4,且x-y+z=36,求x+y+z的值. 已知x/4=y/5=z/6 求x+y+z/3x-2y+z的值 已知x/4=y/5=z/6,求x+y+z/3x-2y+z的值.