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 MRT line an LRT line that goes from Paya Lebar to Buona Vista via Serangoon and Bishan to form Circle line Stage 3 and 4 in 2001. Circle line Stage 5 was finalised in February 2002 when Stage 4 was extended from Buona Vista to World Trade Centre to close up the link and to provide connectivity from the west to Sentosa, and it became the full Circle line in the end. Stations in Circle line that were a part of the original Marina line plans include Dhoby Ghaut, Bras Basah, Esplanade, Promenade, Nicoll Highway and Stadium. The part of the previously