MathDB
Wrong geo?

Source: Iranian second round/Day2/Problem4

May 3, 2019
geometrycircumcircle

Problem Statement

Consider a circle with diameter ABAB and let C,DC,D be points on its circumcircle such that C,DC,D are not in the same side of ABAB.Consider the parallel line to ACAC passing from DD and let it intersect ABAB at EE.Similarly consider the paralell line to ADAD passing from CC and let it intersect ABAB at FF.The perpendicular line to ABAB at EE intersects BCBC at XX and the perpendicular line to ABAB at FF intersects DBDB at YY.Prove that the permiter of triangle AXYAXY is twice CDCD.
Remark:This problem is proved to be wrong due to a typo in the exam papers you can find the correct version [url=https://artofproblemsolving.com/community/c6h1832731_geometry__iran_mo_2019]here.
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