Četverokut
Četverokut ili četverougao je zatvoren geometrijski lik koji ima četiri kuta i četiri stranice. Zbroj svih kutova u četverokutu iznosi 360°.
Podjela četverokuta:
- Varignon and Wittenbauer Parallelograms by Antonio Gutierrez from "Geometry Step by Step from the Land of the Incas"
- Van Aubel's theorem Quadrilateral with four squares by Antonio Gutierrez from "Geometry Step by Step from the Land of the Incas"
- Compendium Geometry Analytic Geometry of Quadrilaterals
- Quadrilaterals Formed by Perpendicular Bisectors
- Projective Collinearity in a Quadrilateral