
Journal for Geometry and Graphics 20 (2016), No. 2, 173184 Copyright Heldermann Verlag 2016 Normal Forms of Triangles and Quadrangles up to Similarity Peteris Daugulis Institute of Life Sciences and Technologies, Daugavpils University, Parades 1, 5400 Daugavpils, Latvia peteris.daugulis@du.lv Vija Vagale Institute of Life Sciences and Technologies, Daugavpils University, Parades 1, 5400 Daugavpils, Latvia The problem of introducing new normal forms of mathematical objects is considered in the case of Euclidean geometry. Normal forms of plane geometry objects such as triangles up to similarity are considered. Several normal forms for triangles and a normal form for quadrangles of special case are described. Normal forms of simple plane objects such as triangles can be used in mathematics education, computations and research. Keywords: Normal forms, similarity, triangle, quadrangle. MSC: 51M04; 97G50, 97D99 [ Fulltextpdf (643 KB)] for subscribers only. 