Analisis Kesulitan Siswa dalam Proses Pemecahan Masalah Geometri Berdasarkan Tahapan Berpikir Van Hiele

Mathematics has an important role in life. However, in the practice of learning some students still regard mathematics as a difficult subject. The evidence in the field shows that the geometry learning result is still low. Difficulties in geometrical matter can affect the difficulties of other parts of the material itself, since many of the subjects in the geometry are interconnected. This study aims to determine the factors causing student difficulties in the process of solving geometry problems based on the stages of thinking Van Hiele and to see students' achievement in understanding geometry based on the stages of thinking geometry Van Hiele. The research method used is qualitative research method with case study research type. Research subjects taken as many as 6 students from class VII C SMP Negeri 6 Garut. The results showed that students' achievement in the process of solving geometry problems based on the stage of thinking Van Hiele at most is at stage 0 (visualization). This is indicated by the high percentage of student achievement in the visualization stage that is as much as 96.87%. The achievement of the best stage of Van Hiele thinking was achieved at 3.13% in stage 1 (Analysis). For stage 2 (informal deduction) and stage 3 (deduction) no students have been able to reach that stage. Factors that cause student difficulties in rectangular material caused by several things, namely the understanding of the concept and the characteristics of the rectangle is lacking, previous understanding of the material wake rectangular flat that is still less strong, the lack of skills to use geometric ideas in solving math problems Relating to wake up quadrilateral, as well as class conditions that are less conducive to learning. Keyword: Student difficulties on geometry, Van Hiele thinking stages, Qualitative, Case Studies