Y by Adventure10, Mango247
Let
be a triangle, and let
and
be the feet of its altitudes issuing from the vertices
and
, respectively. Denote by
the midpoint of the segment
. The circumcircles of triangles
and
have a common point apart from
; denote this common point by
. Prove that:
(a) The point
lies on the circumcircle of the triangle
.
(b) The line
passes through the point
.
(c) We have
.
Darij











(a) The point


(b) The line


(c) We have

Darij