Category:三角形と円に関する定理

Musselman's theorem

Van Schooten's theorem

Cramer–Castillon problem

Van Lamoen circle

Incenter–excenter lemma

Six circles theorem

Euler's theorem in geometry

Carnot's theorem (inradius, circumradius)

Polar circle (geometry)

Fuhrmann circle

Pompeiu's theorem

Kosnita's theorem

Lester's theorem

Lexell's theorem

Harcourt's theorem

Reuschle's theorem

Lune of Hippocrates

Miquel's theorem

Simson line

Thébault's theorem

Griffiths' theorem

Conway circle theorem

Feuerbach's theorem

Thales's theorem

Japanese theorem for cyclic polygons