若|x|=3 ,|y|=4,|z|=5,|a|=6,|b|=8,|c|=10则xyz+abc=?

若3x+7y+z=5,4x+10y+z=3,则x+y+z=? 若x/2=y/3=z/4,则3x-2y+5z/x+y+z= 若x/3=y/4=z/5,求x+y+z/3x-2y+z的值. 若x:y:z=3:4:5=6,求x-y+z分之x+y-z的值 若x+y:y+z:z+x=3:4:5,则x:y:z=?(急,) 若x:y:z=3:4:5且x+y+z=24,求x、y、z的值 若x:y:z=3:4:5 x+y+z=24 求x,y,z的值 若X:y:Z=3:4:5,且X+Y+Z=24,求X、Y、Z的值 若xyz≠0且4(x/z)-5(y/z)=-2,(x/z)+4(y/z)=3,求x:y:z 已知x:：y：z=3：4：5,(1)求x+y分之z的值；（2）若x+y+z=6,求x,y,z. 若实数x,y,z满足x+y+z=4[√(x-5)+√(y-4)+√(z-3)]求x,y,z的值 (x+y):(y+z):(z+x)=3:4:5 3x+y-z=-4已知(x+y):(y+z):(z+x)=3:4:5 ；3x+y-z=-4求x y z (4x-2y-z)-{5x-[8y-2z-(x-2y)]-x-(3y-10z)}=? 设|x|-|y|+|z|=|x+y+z|,且|x+y|=4,|y+z|=5,|y|=3,求(x-y-z)^2的值 1.若3x-2y+z=2;3x+2y+5z=4,求x+22.若x-3y+z=0;3x-3y-4z=0,求x:y:z 若|x-3|+|y+4|+z-5|=0,求代数式x+y-z的值 三元一次方程组题目x+y-z=11 y+z-x=5 x-y+z=1x+y=4 y+z=3 x+z=5若已知x-3y+2z=0 2x+3y-8z=0, 且xyz≠0,则x:y:z= (4x-2y-z)-{5x-[8y-2z-(x+y)]-2(3y-10z)}=?好难啊