Difference between revisions of "2020 IMO Problems/Problem 1"

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Prove that the following three lines meet in a point: the internal bisectors of angles ∠ADP and
 
Prove that the following three lines meet in a point: the internal bisectors of angles ∠ADP and
 
∠P CB and the perpendicular bisector of segment AB.
 
∠P CB and the perpendicular bisector of segment AB.
=Video solution=
+
== Video solution ==
  
 
https://youtu.be/rWoA3wnXyP8
 
https://youtu.be/rWoA3wnXyP8

Revision as of 00:18, 27 September 2020

Problem 1. Consider the convex quadrilateral ABCD. The point P is in the interior of ABCD. The following ratio equalities hold: ∠P AD : ∠P BA : ∠DP A = 1 : 2 : 3 = ∠CBP : ∠BAP : ∠BP C. Prove that the following three lines meet in a point: the internal bisectors of angles ∠ADP and ∠P CB and the perpendicular bisector of segment AB.

Video solution

https://youtu.be/rWoA3wnXyP8

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