3x-5xy+3y/(-x+3xy-y)怎么计算?

【x(xy-xy)-y(x-xy)】÷3xy -x-3xy+y 化简：3x^2-[5xy-(x^y-3xy)+4x^2y-8xy] 因式分解 x-xy+3y-3x 2x+xy-y-4x+5y-6 x^3y(-4y)^2+(-7xy)^2*(-xy)-5xy^3*(-3x)^2 5x^3y*(-3y)^2+(-6xy)^2*(-xy)+xy^3*(-4x^2) 3xy²-5xy³-3y²x+5xy³-x³y 2x²y-3(2xy-xy)-xy 化简3（x²y+xy)-4(x²y-xy)-5x²y, 化简(3x^2-5xy)+{-x^2-[-3xy+2(x^2-xy)+y^2]} X+y=3 xy=-5 Xy=? 5x^2y/-1/2xy*3xy^2 2xy+5y^2+( )=x^2+3xy 已知xy/x+y=3,求代数式3x-5xy+3y/-x+3xy-y的值.已知xy/x+y=3,求代数式3x-5xy+3y/-x+3xy-y的值. 2x平方y-2xy+3xy平方+5+2xy+x平方y-3xy平方-3 过程! 已知x^2-xy=5,xy-y^2=-3求3(x^2-xy)-xy+y^2 已知x^-xy=5,xy-y^=-3,求式子3(x^-xy)-xy+y^的值 计算：5xy^2-[3xy^2-(4xy^2-2x^2y)]+2x^2y-xy^2