已知xy≠0,且3x^2+7xy-6y^2=0,那么x/y的值是.

已知x-y=3xy,且xy不等于0,则-3x+6xy+3y/(7x-5y)-9xy-(3x-y) 已知x-y=4xy且xy≠0,求代数式-x-2xy+y分之2x+3xy-2y的值 已知xy≠0,且2x+3xy-2y=0,求(x+y)/(x-y)的值. 已知x+y=2xy,且xy不等于0,则求-2x+6xy-2y/(7x+5y)-9xy-(3x+y)=___ 已知xy≠0,且3x^2+7xy-6y^2=0,那么x/y的值是. 已知x-7y=0,且y≠0,求2x²﹢xy-3y²分之x²-3xy+y²的值 已知：x^2 + xy - 6y^2=0,且xy不等于0求2x^2-3xy+y^2/5x^2-7xy+2y^2的值 已知x/2=y/3（xy≠0）,求x²-2xy-3y²/x²-6xy-7y²的值 已知xy≠0,且3x^2-2xy-8y^2=0,求x/y的值? 已知,xy≠0,且3x²-2xy-8y²=0,求x/y的值 已知xy≠0,且3x²-2xy-8y²=0,求x/y的值 已知A=5x²y-3xy²+4xy；B=7xy²-2xy+x²y,且x+y=2,x-y=0,化简求-1/2（A+B)-A. 已知x>0,y>0,且x+6y=5根号xy,求(2x+根号xy-y)分之(x+根号xy+2y)的值 已知:x>0,y>0,且x- 10√xy+25y=0,求2x+√xy+3y/x+√xy-y 已知1/x-1/y=2,求3x+7xy-3y/2x-3xy-2y答案是1/x-1/y=2(y-x)/xy=2 得：x-y=-2xy(3x+7xy-3y)/(2x-3xy-2y)=[3(x-y)+7xy]/[2(x-y)-3xy]=(-6xy+7xy)/(-4xy-3xy)=xy/(-7xy)=-1/7 谁能帮我解释一下=[3(x-y)+7xy]/[2(x-y)-3xy]=(-6xy+7xy)/(-4xy-3xy) 是怎 已知xy>0且x≠y,求证：log(x^4+6x^2y^2+y^4)>log(4xy(x^2+y^2)) 已知x>y,且xy 已知x>y,且xy