已知x+y=12,xy=9,求(x+3xy+y)/(xy+xy)的值
已知x+y=12,xy=9,求(x+3xy+y)/(xy+xy)的值
已知x-xy=8,xy-y=-9,求x+y-2xy的值
已知xy^2=-2,求-xy(x^2y^5-xy^3-y)的值.
已知x^-xy=5,xy-y^=-3,求式子3(x^-xy)-xy+y^的值
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.
已知xy/x+y=2,求代数式3x-xy+3y/-x+3xy-y的值
已知xy/x+y =3,求2x-3xy+2y/-x+3xy-y 的值.
已知xy/x+y=3,求2x-3xy+2y/-x+3xy-y的值
已知xy/x+y=6,求3x-2xy+3y/-x+3xy-y的值.
已知x-y=2xy,求代数式3x-5xy-3y/x+xy-y的值
已知y-x-2xy=0,求3x+xy-3y/y-xy-x的值