把4X-4Y=XY化为（4-X)(Y+4)=16怎么化成的?

把4X-4Y=XY化为（4-X)(Y+4)=16怎么化成的? 把方程x平方-2xy+y平方=4化为两个二元一次方程,它们是--------和---------- 把圆X^2+y^2+2X-4Y+1=0化为参数方程 化简:(x+y-4xy/x+y)*(x-y-4xy/x-y)= y=x^2-5x+4化为顶点式 用配方发把y=-2x的平方-4x+2化为顶点式 怎么把x^2/(1/4)+y^2=1化为4x^2+y^2=1的过程? 把方程x-2y=4化为含x的代数式表示y的形式为 已知x*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值? 计算下面式子{x-y+[(4xy)/(x-y)]}{x-y-[(4xy)/(x-y)]} （x-y+4xy/x-y）(x+y-4xy/x-y) (x-y+4xy/x+y)(x+y-4xy/x+y)等于的多少? 谢谢! 化简计算:[x-y+4xy/(x-y)] * [x+y-4xy/(x+y)] 计算:[x-y+4xy/(x-y)] * [x+y-4xy/(x+y)] 化简[x-y+4xy/(x-y)][x+y-4xy/(x-y)] 计算：（x-y+4xy/x-y)(x+y-4xy/x+y) (x一y+4xy/x-y)(x+y-4xy/x+y) (x-y+(4xy/x-y))(x+y-(4xy/x+y)) 分式计算