Y by Adventure10
Let
be the point where the diagonals of a parallelogram
meet. Consider three circles passing through
: the first and the second circles are tangent to
at points
and
, respectively, and the third circle passes through
and
. Denote the points, other than
, where the third circle intersects the first and the second ones by
and
, respectively. Prove that
is tangent to the first and second circles.











