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 Circle Line took delivery of the third of three new vessels constructed by Gladding-Hearn Shipbuilding in Somerset, Massachusetts. In January 2017, Circle Line Sightseeing Cruises purchased New York Water Taxi—among the assets acquired was the latter company's Circle Line Downtown brand, reuniting both Circle Lines under one owner. Circle Line was awarded with proclamations by two New York City mayors. In 1985, then Mayor Ed Koch proclaimed April 23 "Circle Line Day." Approximately 20 years later current Mayor Mike Bloomberg proclaimed September 17 "Circle Line Sightseeing Cruises Day" in 2008. In 2001, Circle Line vessels helped transport victims of the