若|x-y|+(y+3)2=0,则x2+y2-2xy=
若x<y<0,则x2−2xy+y2+x2+2xy+y2=( )
若X2+Y2-2X-6Y+10=0 ,求(x2-y2)/xy的值
已知2x=3y,求xy/(x2+y2)-y2/(x2-y2)的值
已知2x-3*根号(xy)-2y=0(x>0),则x2+4xy-16y2除以2x2+xy-9y2的值是多少?
已知X2-2x+y2+6y+10=0,求(x2-2xy)/(xy+y2)的值
若x2-2xy-y2-x+Y-1=0 求x-y的值
已知实数x、y满足2x2-7xy+3y2=0,求x:y
x(x-1)-(x2-y)=-3,求x2+y2-2xy的值
已知x2+y2-10x-6y+34=0,求(x-y/x+y)2÷x2-y2/xy×x2+2xy+y2/x2-xy 的值.
已知:x=3,y=-5,x2-2xy+y2/x2-y2的值是
设A=2x2-3xy+y2+x-3y,B=4x2-6xy+2y2+4x-y,若|x-3a|+(y+3)2=0,且B-2A
若|x+y-5|+(xy-3)2=0,则x2+y2的值为( )