Pappus and Radical Axis for Problem 5021
The Pappus configuration and two circumcircles used in the generalized solution.
Diagrams
Geometry figure library
A collection of Euclidean-geometry figures, with each configuration and its notation recorded clearly.
Incircle Inversion for Problem 5031
The incircle and auxiliary lines used in the inversion solution.
Tangent Circle in a Parallelogram
The circle centered at M and the auxiliary points used in the proof.
Cyclic Orthocenter Configuration
A representative configuration in which the two equivalent conditions hold.
Auxiliary Rectangle for a Fixed-Point Solution
The auxiliary rectangle and lines used in the solution.