.x-y/2x+y/2x和5/x-5+x/5-xx-y/2x+y/2x5/x-5+x/5-x5x/x²2xy+y²-5y/x²2xy+y²x²/x²-y²-2xy/x-y+y²/x²-y²

5x(x-y)+2y(x-y) 化简:5(x-y)+2(x+y)-3(x-y) (2x+y)²+(x+3y)(x-3y)-x(5x+8y)因式分解 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) （X+2Y)(5X-2Y) (x+2y)(5x-2y) 4x+2y-5x-y (2x-3y)-(5x-y) (2X-3y)-(5x-y) (x-y)^2+5(x-y)-14 (2x-5y)(3x+y) 因式分解(x-2y)(x-3y)+(x-4y)(x-5y)+（x-3y)(x-5y)+(x-2y)(x-4y) 5X+Y=3 X+5Y=2 求x和y.5X+Y=3X+5Y=2求x和y. 因式分解x(x+y)(x-y)-x(x+y)^2 [(x+2y)(x-2y)-(2x-y)^2+(3x-y))2x-5y)]/(-x)我急用 x+y=1 5x-2y=8 3x-y=7 2x-y=3x表示y和用y表示x [(x+2y)(x-2y)-(2x-y)²+(3x-y(2x-5y)]/(-x)的解答 x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2