若x2+y2=25,x+y=7,则x-y=______.
已知x2+4x+y2-2y+5=0,则x2+y2=______.
若实数x,y满足3x2+2y2=6x,则x2+y2的最大值为______.
若x-y=1,x2+y2=25,则xy=______.
若x2-4x+y2+6y+13=0,则x=______,y=______.
x2-y2=55,x-y=5,则x+y=______.
已知x2+y2=25,x+y=7,且x>y,则x-y的值等于______.
若(x+y)2=25,(x-y)2=1,x2+y2的值是______.
若(2x+y)(x-2y)=2x2-mxy-2y2,则m=______.
若x,y∈R且x2+y2=1,则x-y的取值范围为______.
若x+y=10,x3+y3=100,则x2+y2=______.
若x+y=5,xy=6,则x2+y2=______.
若x2+y2=12,xy=4,则x-y=______.