Mar 11
Prove that XY // BC
#Geometry #Circumcircle #PowerOfAPoint #Desargues #USATST #GeometrySolved #ParallelLines
1
6
251
21 Dec 2025
2
122
17 Oct 2025
ABC [inequality PA / BC^2 PB / CA^2 PC / AB^2 >= 1 / R]
#Inequalities #Geometry #Circumcircle #Trigonometry #TrigIdentities #LawOfSines #GeometrySolved
4
165
10 Oct 2025
The best computer problems of the year
#Geometry #ComputerProblems #TangentCircles #EqualAngles #Sharkydevil #Incircle #GeometrySolved
3
184
6 Oct 2025
2 lines and a circumcircle concurrent
#Geometry #Circumcircle #Concurrency #Concurrent #BMO #GeometrySolved #ProjectiveGeometry
5
208
27 Sep 2025
GGG4, P2: Concurrency on Circle with Diameter AH
#Geometry #Circumcircle #GGG4 #GeometrySolved #Inversion #Symmedian #Orthocenter
1
2
247
25 Sep 2025
2019 Iberoamerican Mathematical Olympiad P4
#Geometry #Trapezoid #GeometrySolved #Iberoamerican #ProjectiveGeometry #MiquelPoint #GeometryProposed
4
126
25 Aug 2025
A circle containing nine-point cener
#Geometry #Circumcircle #PerpendicularBisector #Belarus #GeometrySolved #NinePointCenter #EulerLine
3
211
30 Jul 2025
Circumcircle of triangle AQR passes through a fixed point X
#Geometry #Circumcircle #Parallelogram #SpiralSimilarity #GeometrySolved #USATST #FixedPoint
1
7
180
26 Jul 2025
Super Hexagon is an independent twitch video game developed by Terry Cavanagh, w
#Geometry #USEMO #USEMO2021 #GeometrySolved #Hexagon #USA #EulerLine
1
4
171
21 Jun 2025
IMO ShortList 2003, geometry problem 4
#Geometry #Parallelogram #Homothety #Inversion #IMOShortlist #GeometrySolved #Lengths
1
3
207
3 Jun 2025
Miquel circles and a beautiful similarity
#Geometry #Circumcircle #IMOShortlist #GeometrySolved #Reflection #SpiralSimilarity #MiquelPoint
3
240
20 May 2025
1
2
109
15 May 2025
Tangents to a cyclic quadrilateral
#Geometry #Rectangle #Symmetry #Circumcircle #CyclicQuadrilateral #GeometrySolved #ProjectiveGeometry
3
134
7 Apr 2025
APMO 2016: Great triangle
#Geometry #Circumcircle #APMO #GeometrySolved #FunctionalEquation #RightTriangle #Reflection
1
3
198
1 Apr 2025
Poland 2017 P1
#Geometry #Circumcircle #GeometrySolved #MiquelPoint #SpiralSimilarity #AngleChasing #CyclicQuadrilateral
2
3
139
13 Mar 2025
Polish MO Finals 2018, Problem 5
#Geometry #Poland #RadicalAxis #GeometrySolved #ProjectiveGeometry #RadicalAxes #Hi
2
4
996
8 Mar 2025
1
4
778
7 Mar 2025
triangle geometry [AP^2 PD^2 = ...]
#Geometry #Circumcircle #Circumcenter #Triangle #IMOShortlist #Excenters #GeometrySolved
2
6
724
13 Feb 2025
1
5
1,867