2025 IMO Problems/Problem 2
Let and
be circles with centers
and
, respectively, such that the radius of
is less than the radius of
. Suppose circles
and
intersect at two distinct points
and
. Line
intersects
at
and
at
, such that points
,
,
, and
lie on the line in that order. Let
be the circumcenter of triangle
. Line
intersects
again at
. Line
intersects
again at
. Let
be the orthocenter of triangle
.
Prove that the line through parallel to
is tangent to the circumcircle of triangle
.
(The orthocenter of a triangle is the point of intersection of its altitudes.)
Video Solution
Solution from channel Dedekind cuts https://www.youtube.com/watch?v=A4_bYF97IQI
Solution and expansion from channel Olympiad Geometry Club: https://www.youtube.com/watch?v=0TcMSrOYZ7c&t=772s
Solution from Edutube: https://www.youtube.com/watch?v=-Fj7CMJ6iMo
See Also
2025 IMO (Problems) • Resources | ||
Preceded by Problem 1 |
1 • 2 • 3 • 4 • 5 • 6 | Followed by Problem 3 |
All IMO Problems and Solutions |