Centre of the circle lies on y=2 Let the centre of the circle (h,2). Radius of the circle is h (OA)2=(h)2 ⇒(h+1)2+(2−0)2=h2 ⇒h2+2h+1+4=h2 ⇒h=−
5
2
Equation of circle =(x+
5
2
)2+(y−2)2=
25
4
x2+5x+y2−4y+4=0 Point (−4,0) satisfy the equation 16+20+4=0 0=0