From the given data, the centre of the circle is C(3, 2). Since CA and CB are perpendicular to PA and PB, CP is the diameter of the circumcircle of triangle PAB. Its equation is (x − 3)(x −1) + ( y − 2)( y − 8) = 0 or x2+y2 − 4x −10 y +19 = 0.