x+2y+4y^2/x-2y+4x^2y/4y^2-x^2=
x^2-y^2/x+y-4x(x-y)+y^2/2x-y,
{(z+y)(x-y)-(x-y)的2次方+2y(x-y)}除以4y
(2x-y)^2-4(x-y)(x+2y)
(2x-y)²-4(x-y)(x+2y)
化简:(2x-y)²-4(x-y)(x+y)
x+2y+4y^2/x-y+4x^y/4y^2-x^2
4x(y-x)-y^2因式分解
(x+3y-4)(2x-y)
已知4x=9y求(1)x+y/y (2)y-x/2x
{3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1
x+y/2+x-y/3=6,4(x+y)-3(x-y)=-20
{(x+y)/2+(x-y)/3=6 4(x+y)-3(x-y)=-20