y^2-x^2\5x^2-4yx除以x+y\5x-4y

y^2-x^2\5x^2-4yx除以x+y\5x-4y
y^2-x^2\5x^2-4yx除以x+y\5x-4y

y^2-x^2\5x^2-4yx除以x+y\5x-4y
化简：[(y²-x²)/(5x²-4yx)]/[(x+y)/(5x-4y)]
原式=[(y+x)(y-x)/x(5x-4y)]×[(x+y)/(5x-4y)]=(y-x)/x=(y/x)-1.