MathDB
Coaxal Circles

Source: China TSTST Test 2 Day 1 Q3

March 13, 2017
geometrycirclescoaxal

Problem Statement

Let ABCDABCD be a quadrilateral and let ll be a line. Let ll intersect the lines AB,CD,BC,DA,AC,BDAB,CD,BC,DA,AC,BD at points X,X′,Y,Y′,Z,Z′X,X',Y,Y',Z,Z' respectively. Given that these six points on ll are in the order X,Y,Z,X′,Y′,Z′X,Y,Z,X',Y',Z', show that the circles with diameter XX′,YY′,ZZ′XX',YY',ZZ' are coaxal.
Back to ProblemsView on AoPS