The point from which the tangents to the circles x2+y2–8x+40=0,5x2+5y2–25x+80=0,x2+y2–8x+16y+160=0 are equal in length is
Required point is the radical centre of the three given circles. The radical axes of these three circles taken in pairs are
3x – 24 = 0, 16y + 120 = 0, 3x + 16y + 80 = 0
∴ x = 8, y =−152