Irina BOGATYREVA THE INITIAL STAGE OF TEACHING PROOF IN MATHEMATICS COURSE Klavdia BORISOVA TESSELLATION WITH SOME IRREGULAR POLIGONS Dobrinka BOYKINA, Vassil MILLOUSHEV, Roumyana MAVROVA SOME APPLICATIONS OF THE GRAPHIC METHOD Toni CHEHLAROVA, Evgenia SENDOVA ALONG THE TRACES OF THE CONIC SECTIONS Sava GROZDEV, Vesselin NENKOV TWO REMARKABLE POINTS OF THE TRIANGLE GEOMETRY Samet KARAIBRYAMOV, Bistra TSAREVA ONE APPLICATION OF THE INFORMATICS IN THE DESCRIPTIVE GEOMETRY Ivanka MARASHEVA–DELINOVA THE BEGINNING OF A PARTNERSHIP IN THE PROCESS OF STUDYING MATHEMATICS Ivanka MARASHEVA–DELINOVA, Emil DELINOV SOME ASPECTS OF THE THEME “INFORMATION PLATFORM” IN THE TRAINING OF STUDENTS IN ECONOMIC MAJORS Vassil MILLOUSHEV, Dobrinka BOYKINA ON THE MASTERING OF KNOWLEDGE AND SKILLS FOR SOLVING MATHEMATICAL PROBLEMS IN THE CONTEXT OF THE RELATIONSHIP “REFLECTION – SYNERGY” Penka RANGELOVA, Ivaylo STARIBRATOV EXPERIMENTING WITH DIFFERENT APPROACHES TO TEST COLINEARITY OF POINT