2x2+xy-y2-4x+5y-6怎么算,thanks

2x2+xy-y2-4x+5y-6怎么算,thanks 2x2+xy-y2-4x+5y-6 因式分解 x2-2xy+y2=4 x2+y2-x-y=6 解不等式x2-2xy+y2=4 x2+y2-x-y=6 解不等式 已知x2+4y2+x2y2+1=6xy,则(x4-y4)/(2x2+xy-y2)*(2x-y)/(xy-y2)/(x2+y2/y)2= 因式分解 2x2+xy-y2-4x+5y-6 x2-y2+a2-b2+2ax+2by 3x2+5xy-2y2+x+9y-4 b4-2b2-82x2+xy-y2-4x+5y-6x2-y2+a2-b2+2ax+2by3x2+5xy-2y2+x+9y-4b4-2b2-8 已知x2+y2+4x-2y+5=0,求x2+2xy+y2值 4x2-y2/x2-2xy+y2 +(2x-y)/2x2-2xy 计算(x+y/x-y + 4xy/y2-x2)(x2-9y2)/（x2+2xy-3y2） xy-1+x-y 十字相乘法因式分解怎么做啊xy-1+x-y x2y-3xy-2x+6 3x2+4xy+y2 X2+Y2+8X+6Y+25=0 求代数式(x2-4y2/x2+4xy+4y2)-x/x+2y 已知X2+Y2+8X+6Y+25=0 求代数式X2++XY+4Y2分之X2-4Y2 减X+2Y分之X的值 因式分解：3x2+5xy-2y2+x+9y-4 x2+x-(a2-a) 3x2+4xy-y2 x,y,a后面的2表示平方 分解因式 2x2+xy+y2-4x+5y-6 x2-4y2-3xy+y+x 分解因式 （1）32+5xy-2y2+x+9y-4 （2）2x2+xy-y2-4x+5y-6 (3)3x2+4xy-y2 X3+9+3X2+3X分解因式 2X2+XY-Y2-4X+5Y-6分解因式 x2－(a＋b)xy+aby2 x2+4xy－5y2 x2－5x+3 2x2+xy－y2－4x+5y－6 解方程组(1):xy-y-2x+2=0 (2):x2-2x+y2-4x=-5方程组:xy-y-2x+2=0: x2-2x+y2-4x=-5怎么解?