已知x^2+xy=12,且xy+y^2=13,求x^2+y^2

已知x^2+xy=12,且xy+y^2=13,求x^2+y^2 已知x-y=4xy且xy≠0,求代数式-x-2xy+y分之2x+3xy-2y的值 已知x^2+xy=13,且xy+y2=12,求(x+y)(x-y)和（x+y）^2 已知x^2-xy+3y^2=0 且xy不等于0 求x/y+y/x 的值 已知xy≠0,且2x+3xy-2y=0,求(x+y)/(x-y)的值. 已知x^2-7xy+12y=0,且x.y不等于0,求x^2-2xy+y^2/2xy的值 已知xy>0,且X平方y=2,求x平方+xy的最小值 已知x-xy=8,xy-y=-9,求x+y-2xy的值 已知x>0,y>0,且x+6y=5根号xy,求(2x+根号xy-y)分之(x+根号xy+2y)的值 已知x,y是实数,且适合方程(xx+xy-12)(xx+xy-12)+(xy-2yy-1)(xy-2yy-1)=0求x, 已知xy^2=-2,求-xy（x^2y^5-xy^3-y)的值. 已知xy^2=-2 求-xy(x^2y^5-xy^3-y)