已知x+y=8,y+x=12,x+z=10,则x+y+z等于几?
已知X+Y=12 Y+Z=10 求X Y Z各等于几
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)(x-y+z)=
已知x+y=3,y+z=4,x+z=5,则x+y+z等于( )
X-Y=Z X+Y+Z=80已知Y等于10求X和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x+y=8,y+z=12,x+z=10,那么x+2y+z等于多少呢?
若{x+3y+10z=0 则 (x+y-z)/(x-y+z)
已知:(x+y)/z=(x+z)/y=(z+y)/x,且xyz不等于0,则分式(x+y)(x+z)(z+x)/xyz的值
X+Y+Z=?
三元一次方程组,x+y+z=26x-y=12x-y+z =18 求x,y,z各等于几