已知x y=3,xy=-7求x² y²
已知xy²=-6,求xy(x^3y^7-3x^2y^5-11.5y)的值
已知A=3x²y-xy²,B=xy-3x²y,且|x-1|+(y+3)²=0,求
已知|x+2|+(y+3)²=0,求6xy²-[3x²y-(2x²y-xy
已知x+y=3,xy=-4分之7,求x²-y².
已知(x+y-7)²+|2x-3y-4|=0 求xy得值
已知x+y=3,xy=-4分之7,求x-y和x²-y²的值
已知x/2=y/3(xy≠0),求x²-2xy-3y²/x²-6xy-7y²的值
已知x/y=3,求(x²+2xy-3xy²)/(x²-xy+y²)
已知x:y=3:2,求(x²+3xy)/(xy+2xy)
已知x/y=3,求x²+2xy-3y²/x²-xy+y²
已知y分之x=3,求x²-xy+y²分之x²+2xy-3y²
已知x/y等于3,求x²+2xy-3y²/x²-xy+y²的值