若4x-5y=0,且xy≠0则(2x-5y)/(2x+5y)=
若(x*x+y*y)(x*x+y*y)-4x*x*y*y=0,求代数式(x*x+5xy+y*y)/(x*x+2xy+y*
若x>0,y>0,且√x(√x+√y)=3√y(√x+5√y),求(2x+2√xy+3y)/(x-√xy+y)的值.
已知(x+2)^2+|x+y+5|=0,求3x^2y-[2x^2y-(2xy-x^2y)-4x^2]-xy
已知5x-4y=0且xy不等于0,求x^2+y^2/x^2-y^2-x+y/x-y的值
已知x²-xy-y²=0,且x≠0,y≠0.求代数式(x²-2xy-5y²)/(
若(x-4y)(x+3y)=0 且xy>0 则分式x+3y/2x-y的值为
已知x^2+y^2-4x+6y+13=0求(xy+y^2/5x^2-5xy+xy+y^2)·(5/x+y)-(y/x-y
若x,y∈R+,且2x+8y-xy=0,则x+y的最小值为( )
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
若(3xy+2)+|7-x-y|=0,求代数式(5xy+10y)-[-5x-(4xy-2y+3x)]的值.
已知x-y=3xy,且xy不等于0,则-3x+6xy+3y/(7x-5y)-9xy-(3x-y)
已知x,y>0 2x+y+3=xy 求5x+4y最小值