Power of a point P intersects the circle at A and B, the endpoints of the diameter. Their respective products of distances are equal to each other and to the power of point P in that circle This equality is sometimes known as the ""secant-tangent theorem"", ""intersecting chords theorem"", or the ""power-of-a-point theorem"". The power of a point is used in many geometrical definitions and proofs. For example, the radical axis of two given circles is the straight line consisting of points that have equal power to both circles. For each point on this line, there is a unique circle centered on that point
Circle Line Sightseeing Cruises location. In 1962 it bought the famous and venerable Hudson River Day Line, keeping it as a separate brand until 1985. In 1981, the Circle Line split into two companies—Circle Line Sightseeing Cruises and Circle Line Downtown. In 1988 the 42nd Street company bought World Yacht's operating upscale dining cruises from Chelsea Piers - currently World Yacht Dining Cruises. In 1998 the 42nd Street company also launched The Beast, a speedboat ride which takes tourists around the Statue of Liberty and goes 45 mph. In 2007, the United States National Park Service said it was going to terminate Circle Line