Three Equal Segments from the Altitudes of a Triangle

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In the triangle let the feet of the altitudes be
,
, and
. The circle with diameter
meets
and
at two points other than
to form a segment of length
; similarly define
and
. Prove that
.
Contributed by: Jaime Rangel-Mondragon (July 2013)
Open content licensed under CC BY-NC-SA
Snapshots
Details
The segments of equal length are drawn in blue.
This Demonstration comes from problem 19 of the shortlisted problems for the 1971 International Mathematical Olympiad (IMO).
Reference
[1] D. Djukić, V. Janković, I. Matić, and N. Petrović, The IMO Compendium, 2nd ed., New York: Springer, 2011 p. 73.
Permanent Citation
"Three Equal Segments from the Altitudes of a Triangle"
http://demonstrations.wolfram.com/ThreeEqualSegmentsFromTheAltitudesOfATriangle/
Wolfram Demonstrations Project
Published: July 11 2013