Elementary Synthetic Geometry

altitude angle equal angle-bisector angles opposite axis of symmetry bisects Brocard p't called cenquad circumcenter co-straight coincide common point concurrent concyclic congruent Corollary corresponding cross ratio diameter draw end point equal angles equal sects equal sides equiangular polygon explemental exterior angle figure g-line given p't given point given straight greater harmonic conjugates harmonic range inscribed inscribed angles intercept intersection point Inversely isogonal isogonal conjugates Lemoine p't Lemoine point lune magnitude median meet mid p't mid point opposite sides orthocenter parallel parallelogram perigon perspective plane point in common polar pole polygon Proof quad quadrant quadrilateral radius rectangle rhombus right angles rotation sect joining semicircle sides equal sphere spherical angle spherical polygon spherical triangle square st's straight angle supplemental symcentral symmedians symmetrical with regard symtra tangent Theorem third side transversal vertex vertices