已知4x-3y-6z=0,x+2y-7z=0(x,y,z均不为0) ,求(2x+3y+6z)/(x+5y+5z)的值
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![已知4x-3y-6z=0,x+2y-7z=0(x,y,z均不为0) ,求(2x+3y+6z)/(x+5y+5z)的值](/uploads/image/z/591085-37-5.jpg?t=%E5%B7%B2%E7%9F%A54x-3y-6z%3D0%2Cx%2B2y-7z%3D0%28x%2Cy%2Cz%E5%9D%87%E4%B8%8D%E4%B8%BA0%29+%2C%E6%B1%82%282x%2B3y%2B6z%29%2F%28x%2B5y%2B5z%29%E7%9A%84%E5%80%BC)
已知4x-3y-6z=0,x+2y-7z=0(x,y,z均不为0) ,求(2x+3y+6z)/(x+5y+5z)的值
已知4x-3y-6z=0,x+2y-7z=0(x,y,z均不为0) ,求(2x+3y+6z)/(x+5y+5z)的值
已知4x-3y-6z=0,x+2y-7z=0(x,y,z均不为0) ,求(2x+3y+6z)/(x+5y+5z)的值
4x-3y-6z=0...(1)
x+2y-7z=0...(2)
(2)*4-(1):
11y=22z
y=2z
代入(2):x+4z-7z=0
x=3z
将y=2z,x=3z代入(2x+3y+6z)/(x+5y+5z)
=(6z+6z+6z)/(3z+10z+5z)
=18z/18z
=1