已知:4x-3y-6z=0,x+2y-7z=0,且x,y,z都不为零.求3x+2y+zx+2y+3z
已知4x-3y-6z=0,x+2y-7z=0,且x、y、z都不为0,求(3x+2y+z)/(x+2y+3z)的值 快帮求
已知3x-2y-5z=0,2x-5y+4z=0,且x,y,z都不为0,求(3x*x+y*y+4z*z)/(5x*x+y*
已知3x-2y-5z=0,2x-5y+4z=0,且x,y,z均不为0,求3x*x+2y*y+5z*z/5x*x+y*y-
已知4x-3y-6z=0 ① ,x+2y-7z=0 ②,且x,y,z均不为0,求3x+2y+z÷x+2y+3z的值
已知2x-3y-z=0,x+3y-14z=0,且x,y,z不全为0,求4x的平方-5xy+z的平方/xy+yz+zx的值
x+y+z+sin(x+2y+3z)=0,求Zx偏导.
已知有理数x、y、z满足条件|x-z-2|+(3x-6y-7)^2+|3y+3z-4|=0,求x、y、z
已知x/2=y/3=z/4,且x+y+z不等于0,求2x+3y-4z/x+y+z的值
已知x,y,z均不为0,且满足方程组x+y-z=0,2x-y-5z=0试求2x+y+3z/3x-y-z
已知x,y,z均不为0,且满足方程组{x+y-z=0,①2x-y-5z=0.②试求(2x+y+3z)/(3x-y-z)值
已知4x-3y-6z=0,x+2y-7z=0,且x,y,z≠0,求2x+3y+6z/x+5y+5z的值.
已知3x-2y-5z=0,2x-5y+4z=0,且x.y.z均不为0,求3x^2+2y^2+5z^2/5x^2+y^2-