已知x+4y-2x+8y+5=0,求x^4-y^4/2x+xy-y·2x-y/xy-y÷(x+y/y)的值.数学上交不不算请教下.

已知:3x-5y=0,求x/y,x-y/y,x-y/x 已知X.x+y.y-4x+2y+5=0,求4X.X-12X Y+9Y.y的值 已知x^2+4y^2-4x+8y+8=0,求x+y 已知4x^2+y^2-4x+4y+5=0,求x,y 已知x²+4x+y-2y+5=0求x+2y 已知x²+y²-2x+4y+5=0,求x+y 已知x,y>0 2x+y+3=xy 求5x+4y最小值 已知x^2+4y^2-2x-2x+8y+5=0,求x^2-y^2/2x^2+xy-y^2*2y-y/xy-y/(x^2+y^2/y)^2的值 已知X*X+Y*Y+6X-8Y+25=0 求（Y/X)+(X/Y)-2=? 已知X^2+Y^2-2X-4Y+5=0,求分式Y/X-X/Y的值 已知x²+y²-2x-4y+5=0,求分式y/x-x/y的值. 已知x、y满足x²+y²+2x-4y+5=0,求x、y的值 已知x*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值? 已知7x+5y/2y-x=3/2,且x≠0,求X/x-4y 已知x.x+y.y+8x+6y+25=0,求代数式(x.x-4y.y)/(x.x+4xy+4y.y)-x/(x+2y)的值 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) 已知5x-4y=0,求x:y和x+y:y的值 已知x+4y-2x+8y+5=0,求x^4-y^4/2x+xy-y·2x-y/xy-y÷(x+y/y)的值.数学上交不不算请教下.