x^+3xy - 10y^ - x+9y - 2 .

(x-2xy)*(-xy+2y*y)-(3x*x-2xy)(x-9xy+6y*y) 化简：x-y/x+3y÷x^-y^2/x^2+6xy+9y^2-(xy/x+y) [-(x-y)^2/xy]^-4*(y^2-xy/x)^3*(x^4/y^10)÷(xy-y^2/x)^-5=-y(y- 已知2x+xy=10,3y+2xy=6.求4x+8xy+9y=? (x+y)(x-y)-(2xy+3y)平方 [x(x^2y^2-xy)-y(x^2-x^3y)]/3x^2y 1、(-7x^y)(2x^y-3xy^3+xy) 2、((x-y)^6)/((y-x)^3)/(x-y) 数学题(x+y+3)(x^2+y^2+2xy-3x-3y+9) 9xy(x-y)(x+1)-3y(x-y)(3x+2y)+6y的平方(x-y)(x+1),因式分解 x^2-xy-6y^2+3xy+y+2 因式分解：4a^2(x-y)+9(y-x) -4x^2y^2+x^3y+4xy^3 x^2-3xy-10y^2+x+9y-2