Y by rocketscience, NJOY, amar_04, GeoMetrix, mijail, CyclicISLscelesTrapezoid, Adventure10, Mango247, Rounak_iitr
Let
be a triangle and let
and
be variable points on sides
and
, respectively, such that
. Let
denote the point on
such that
is parallel to
, and let
denote the point on
such that
is parallel to
. Prove that as
vary, the circumcircle of
passes through a fixed point, other than
.
Proposed by tworigami

















Proposed by tworigami