MathDB

4

Part of 2016 Regional Olympiad of Mexico West

Problems(1)

2 angle bisectors concurrent with a line, AD = DE, BC = EC

Source: Mathematics Regional Olympiad of Mexico West 2016 P4

9/7/2022
Points A,B,CA, B, C and DD lie on a circle, in that order clockwise, such that there is a point EE on segment CDCD with the property that AD=DEAD = DE and BC=ECBC = EC. Prove that the intersection point of the bisectors of the angles ∠DAB\angle DAB and ∠ABC\angle ABC is on the line CDCD.
geometryconcurrencyconcurrent