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USAMO 2010 — Days 1 and 2 Question 4

USAMO · USAMO 2010 — Days 1 and 2

Question 4

Let $ABC$ be a triangle with $\angle A = 90^\circ$.
Points $D$ and $E$ lie on sides $AC$ and $AB$, respectively,
such that $\angle ABD = \angle DBC$ and $\angle ACE = \angle ECB$.
Segments $BD$ and $CE$ meet at $I$.
Determine whether or not it is possible for segments $AB$, $AC$, $BI$, $ID$, $CI$, $IE$
to all have integer lengths.


Proposed by Zuming Feng (credit in the supplied third-party notes).