MathDB
equal segments , incenter and circumcircle related

Source: 1998 Estonia National Olympiad Final Round grade 9

March 11, 2020
geometryincentercircumcircleequal segments

Problem Statement

Let SS be the incenter of the triangle ABCABC and let the line ASAS intersect the circumcircle of triangle ABCABC at point DD (DAD\ne A). Prove that the segments BD,CDBD, CD and SDSD are of equal length.