已知xy=8满足x²y-xy²-x+y=56,求x²+y²的值
已知xy=8,满足x²y-Xy²-x+y=56,求x²+y²的值.
已知非零有理数x,y满足x²-4xy+4y²=0,求x-y/x+y-y-x/x+y的值.
已知实数x、y满足x²y+xy²=20,xy+x+y=9,求x²+y²的值.
若正数x,y满足x²-y²=2xy,求(x-y)/(x+y)的值
正数x,y满足x²-y²=2xy,求x-y/x+y的值
已知实数xy满足x²﹢y²-xy+2x-y+1=0求xy
已知实数x,y满足x²+y²-xy+2x-y+1=0 求x y
已知x,y满足x(+1)-(x²+2y)=1,求x²+4xy+4y²-2x+4y的值.
已知x+y=4.x-y=6.求代数式xy(y²+y)-y²(xy+2x)-3xy的值
已知x/y=2,求x²-xy+3y²/x²+xy+6y²的值
已知x/y=3,求x²+2xy-3y²/x²-xy+y²的值
已知y/X=3,求x²-xy+y²/x²+2xy-3y²的值