🌐EnglishEnglishEspañolFrançaisItalianoPortuguêsTürkçeالعربية日本語EntityQ743775· pop 11· linked from 159 articlesPtolemy's inequalityinequality relating the six distances between four points on a planeAvailable in 11 languagesEspañolFrançais日本語ItalianoالعربيةGreekKhmerMacedonianTürkçeConnectionsElementsEntityDiophantus of AlexandriaEntityCategoriesAncient Greek mathematicsGeometric inequalitiesPtolemy