{上面x/2=y/3=z/5下面2x+y+3z=88,{上面x/2=y/3=z/5下面2x+y+3z=88,

{上面x/2=y/3=z/5下面2x+y+3z=88,{上面x/2=y/3=z/5下面2x+y+3z=88, X/(Y-Z)+Y/(Z-X)+Z/(X-Y)=0求证X/(Y-Z)^2+Y/(Z-X)^2+Z/(X-Y)^2=0通过上面求证下面^2是……的2次方X/(Y-Z)^2+Y/(Z-X)^2+Z/(X-Y)^2=0 x/2=y/3=z/5 x+3y-z/x-3y+z 3x+4y+z=14 x+5y+2z=17 2x+2y-z=3 第一题（上面是） 9x-5y+z3x+4y+z=14x+5y+2z=172x+2y-z=3第一题（上面是）9x-5y+z=-69x+y+4z= 3-9x+3y-5z=0第二题解方程组 已知x-y/x+y=y+z/2(y-z)=z+x/3(z-x),求证8x+9y+5z=0THX.. 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+z)=x,(y+z)(y+x)=2y,(z+x)(z+y)=3z,求x,y,z (4x-2y-z)-{5x-[8y-2z-(x-2y)]-x-(3y-10z)}=? 解一下下面这两道三元1次方程2x+3y-z=112x+y-5z=8-2x+7y+z=19 方程组{上面的4x+3y=17下面2x+5y=19 (4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuaihuajian 设|x|-|y|+|z|=|x+y+z|,且|x+y|=4,|y+z|=5,|y|=3,求(x-y-z)^2的值 x+y=5 2x+3y-z=9 x-y+z=4 已知x/y+z=y/x+z=z/x+y,分式(x+2y+3z)/(2x+5y-2c)有意义时的值 x+y+z=35 2x-y=5 y/3=z/2 求x,y,z (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 x+2y=3x+2z=4y+z 求x:y:z