若X/10=Y/8=Z/9则X+Y+Z/Y+Z=?

若X/10=Y/8=Z/9则X+Y+Z/Y+Z=? X/10=Y/8=Z/9,则X+Y+Z/2Y-3Z 若x除以10=y除以8=z除以9,则x+y+z除以y+z 若x+y=8 y+z=12 x+z=10 则x+y+z =多少 解方程组：{x(x+y+z)=6 {y(x+y+z)=9 {z(x+y+z)=10 x+y=8 y+z=12 x+z=10 x+y+z= x+y=8 y+z=12 x+z=10 x+y+z= 若x+y+z=3y=2z,则x/x+y+z=? 若x,y,z成等差数列,则(z-x)^2-4(x-y)(y-z)= 若整数x、y、z满足（9/8）^x×(9/10)^y×(16/15)^z=2 ,则x=____ y=____ z=___ 若x、y、z、满足（9/8）^x ×（10/9）^y×（16/5）^z=2,则x、y、z、的值为多少 (x+y-z)(x-y+z)= 已知x-y/x+y=y+z/2(y-z)=z+x/3(z-x),求证8x+9y+5z=0THX.. 已知x+y=8,y+z=12,x+z=10,则x+y+z=? 若x+y+z=2,x^2-（y+z）^2=8,则x-y-z=多少? 若x-y+z=-4,x^2-(y+z)^2=8,则x+y+z=如题 若3x+7y+z=5,4x+10y+z=3,则x+y+z=? 若x、y、z均不等于0,且2x+y-z=0 x+8y+2z=0,则x:y:z=?