Question

直线2x+y+2=0和x-2y+1=0的交点为圆心,经过(2,3)的圆的方程?

Answer 1

x=2y-1;

2(2y-1)+y+2=0;

y=0;

x=-1;

(x-2)^2-(y-3)^2=[2-(-1)]^2+[3-0]^2;

(x-2)^2-(y-3)^2=18;