方程x2=x的解是______;(x2+y2)2-4(x2+y2)-5=0,则x2+y2=______.
x2=x,
变形得:x2-x=0,即x(x-1)=0,
解得:x1=0,x2=1;
(x2+y2)2-4(x2+y2)-5=0,
分解因式得:(x2+y2-5)(x2+y2+1)=0,
解得:x2+y2=5,x2+y2=-1(舍去),
则x2+y2=5.
方程x2=x的解是______;(x2+y2)2-4(x2+y2)-5=0,则x2+y2=______.
x2=x,
变形得:x2-x=0,即x(x-1)=0,
解得:x1=0,x2=1;
(x2+y2)2-4(x2+y2)-5=0,
分解因式得:(x2+y2-5)(x2+y2+1)=0,
解得:x2+y2=5,x2+y2=-1(舍去),
则x2+y2=5.