若xyz不等于0,且x+2y-7z=0,4x-3y-6z=0,求(2x^2+3y^2+6z^2)除以(x^2+5y^2+7z^2)的值?就现在啊.会多给分的.

若xyz不等于0,且(y+z)/x=(z+x)/y=(x+y)/z,求(y+z)(z+x)(x+y)/xyz的值? 若xyz不等于0,且满足(y+z)/x=(x+z)/y=(x+y)/z,求（y+z)（x+z)（x+y)/xyz的值 若xyz不等于0,且满足(y+z)/x=(x+z)/y=(x+y)/z,求（y+z)（x+z)（x+y)/xyz的值 已知xyz不等于0,且x+2y-z=0,7x-y-z=0,求x+y+z/2x-y-z的值. 若(4x-3y-3z)^2+|x-3y-z|=0 且xyz不等于0 则4x+y-z/x+y+z 的值 若xy-z不等于0,且(y+x)/x=(z+x)/y=(y+x)/z,求[(y+z)(z+x)(x+y)]/xyz的值? 已知xy/5=y+z/6=z+x/7,且xyz不等于0,求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的值为? 若xyz不等于0,且{4x-5y+2z=0,x+4y-3z=0,求x:y:z 若xyz不等于0,且4x-5y+2z=0,x+4y-3z=0,求x：y：z的值. 若xyz不等于0,且|2x+3y-z|+(3x-y-z)^=0,则代数式z分之x+y= 若xyz不等于0,且x+2y-7z=0,4x-3y-6z=0,求x+2y+z/x-2y-z的值? 已知方程组4x-y+3z=0 2x+y+6z=0且xyz不等于0,则x/y+y/z+z/x是多少 若x+y+z=0且xyz不等于0,求x(1/y+1/z)+y(1/x+1/z)+z(1/x+1/y)的值 若xyz不等于0,且{4x-5y+2z=0,x+4y-3z=0,求31x+19y-23 若xyz不等于0,且绝对值2x+3y-z+(3x-y-z）的平方=0,则代数式x+y/zkuai 初二比例线段及性质的题若 X/2 = Y/3 = Z/5 ,且XYZ不等于0,则X+Y+Z/3X-Y = 请说明:若X^2 + 2Y^2 + Z^2=XY-YZ-XZ,且XYZ不等于0,则X=Y=-Z