Abscissa and ordinate Abscissa and ordinate In mathematics, the abscissa (; plural "abscissae" or "abscissæ" or "abscissas") and the ordinate are respectively the first and second coordinate of a point in a coordinate system. The abscissa of a point is the signed measure of its projection on the primary axis, whose absolute value is the distance between the projection and the origin of the axis, and whose sign is given by the location on the projection relative to the origin (before: negative; after: positive). The ordinate of a point is the signed measure of its projection on the secondary axis, whose absolute value
Extremal graph theory was 1975 when Szemerédi proved his result a vital tool in attacking extremal problems. A typical result in extremal graph theory is Turán's theorem. It answers the following question. What is the maximum possible number of edges in an undirected graph "G" with "n" vertices which does not contain "K" (three vertices "A", "B", "C" with edges "AB", "AC", "BC"; i.e. a triangle) as a subgraph? The complete bipartite graph where the partite sets differ in their size by at most 1, is the only extremal graph with this property. It contains edges. Similar questions have been studied with various