(3x+y=17 x+y+z=8 2y=z)

(3x+y=17 x+y+z=8 2y=z) 已知(x+y)(x+z)=x,(y+z)(y+x)=2y,(z+x)(z+y)=3z,求x,y,z 试证明(x+y-2z)+(y+z-2x)+(z+x-2y)=3(x+y-2z)(y+z-2x)(z+x-2y) 已知x-y/x+y=y+z/2(y-z)=z+x/3(z-x),求证8x+9y+5z=0THX.. (4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuaihuajian (4x-2y-z)-{5x-[8y-2z-(x-2y)]-x-(3y-10z)}=? X/10=Y/8=Z/9,则X+Y+Z/2Y-3Z 解方程 x+y+z=10,x+3y+2z=17,y-x+3z=8 (4x-2y-z)-{5x-[8y-2z-(x+y)]-2(3y-10z)}=?好难啊 证明 ：x/(y+z)+y/(z+x)+z/(x+y)>=3/2其中 x,y,z>0 方程组x+3y-z=17 2x-y+z=16中的y、z同时满足y=z+2,求x、y、z.急! x+y/2=z+x/3=y+z/4 x+y+z=27 若x+y+z=3y=2z,则x/x+y+z=? (x+y-z)(x-y+z)= x/2=y/3=z/5 x+3y-z/x-3y+z x+2y=3x+2z=4y+z 求x:y:z (x*x+2)(y*y+4)(z*z+8)=64xyz,求x,y,z 急 x,y,z均为正整数,x>=y,y>=z,z>=8 x+3y-z=急x,y,z均为正整数,x>=y,y>=z,z>=8x+3y-z=132,请问1.x+y+z有最小值782.x+y+z有最大值1343.洽有一组解(x,y,z)使得x+y+z有最大值4.x+3y有最小值1405.x+2y有最大值130