x2+y2-2x-4y=0,2x-y-4=0

x2+y2-2x-4y=0,2x-y-4=0
x2+y2-2x-4y=0,2x-y-4=0

x2+y2-2x-4y=0,2x-y-4=0
y=2x-4
x^2+(2x-4)^2-2x-4(2x-4)=0
5x^2-26x+32=0
(5x-16)(x-2)=0
x=16/5,y=12/5
或x=2,y=0

x^2+y^2-2x-4y=0
2x-y-4=0
y=2x-4
带入第一个式子得x=2或x=16/5
那么y=0或12/5