> 51-XX Geometry > 51MXX Real and complex geometry

51M04 Elementary problems in Euclidean geometries	51M05 Euclidean geometries (general) and generalizations	51M09 Elementary problems in hyperbolic and elliptic geometries
51M10 Hyperbolic and elliptic geometries (general) and generalizations	51M15 Geometric constructions	51M16 Inequalities and extremum problems
51M20 Polyhedra and polytopes; regular figures, division of spaces	51M25 Length, area and volume	51M30 Line geometries and their generalizations
51M35 Synthetic treatment of fundamental manifolds in projective geometries (Grassmannians, Veronesians and their generalizations)	51M99 None of the above, but in this section

51MXX Real and complex geometry