y^2+y-20x^2-x-6(x+2)(x-4)-7

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 4(x+y)-3(x-y)=-20,2/x+y+3/x-y=6 x^8-x^7y+x^6y^2-x^5y^3+x^4y^4-x^3y^5+x^2y^-xy^7+y^8 y^2+y-20x^2-x-6(x+2)(x-4)-7 1、x(x-y)(x+y)-x(x+y)^2 若2x-3y+4=0则x（x*x-1)+x(5-x*x)-6y+7 x^2-y^2/x+y-4x(x-y)+y^2/2x-y, 六道因式分解的题.(x+y)^4+(x+y)^2-20(x^2+7x+6)(x^2+7x-8)+45(x-1)(x+2) 化简(x+y)-(2x+y/2)-(3x+y/6)-(4x+y/12)-(5x+y/20)-……-(10x+y/90) 因式分解3x^2(x-y)+6x(y-x) 2(y-x)的平方-7(x-y)+6(x-y)-3(y-x)的平方