由x+y-3=0 得:(x-2)=-(y-1)
代入(x-2)^2+(y-1)^2=20/3得:
2(x-2)^2=20/3
2(y-1)^2=20/3
∴x=2+根号10/3,y=1-根号10/3
x=2-根号10/3,y=1+根号10/3