若 x/3y = y/2x-5y =6x-15y/x求4x^2-5xy+6y^2/x^2-2xy+3y^2的值?

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若x/3y=y/2x-5y=6x-15y/x求4x^2-5xy+6y^2/x^2-2xy+3y^2的值?若x/3y=y/2x-5y=6x-15y/x求4x^2-5xy+6y^2/x^2-2xy+3y^

若 x/3y = y/2x-5y =6x-15y/x求4x^2-5xy+6y^2/x^2-2xy+3y^2的值?
若 x/3y = y/2x-5y =6x-15y/x
求4x^2-5xy+6y^2/x^2-2xy+3y^2的值?

若 x/3y = y/2x-5y =6x-15y/x求4x^2-5xy+6y^2/x^2-2xy+3y^2的值?
因为
x/(3y)=y/(2x-5y)
所以
(x+y)/(3y+2x-5y)=x/(3y) --等比性质
化简得
2x^2-5xy-3y^2=0
(x-3y)*(2x+y)=0
x=3y or y=-2x
当x=3y时,原式=9/2
当y=-2x时,原式=38/17
所以值为9/2或38/17

不晓得啊。。。