Similar to 垂重円

Circumgon

Encyclopedia of Triangle Centers

Apollonius point

Circles of Apollonius

De Longchamps point

Circumcircle

Incircle and excircles

Malfatti circles

Taylor circle

1 + 1 + 1 + 1 + ⋯

1/2 + 1/4 + 1/8 + 1/16 + ⋯

1/2 − 1/4 + 1/8 − 1/16 + ⋯

1/4 + 1/16 + 1/64 + 1/256 + ⋯

Hundredth

Catalogue of Triangle Cubics

Apollonian circles

Problem of Apollonius

Twin circles

Circular sector

Golden triangle (mathematics)

Orthocenter

Medial triangle

Obtuse triangle

Inscribed circle

Brocard points

Reuleaux triangle