The equation of a circle which cuts the three circles
x2 + y2 − 3x − 6y + 14 = 0,
x2 + y2 − x − 4y + 8 = 0
x2 + y2 + 2x − 6y + 9 = 0
orthogonally is –––––––––––––––
Find the equation of circle circumscribing the quadrilateral formed by four lines 3x + 4y − 5 = 0, 4x − 3y − 5 = 0, 3x + 4y + 5 = 0 and 4x − 3y + 5 = 0