Investigating Student’s Mathematical Reasoning Ability by Using PMRI Based on Emergent Modeling

Mathematics and reasoning are two things that cannot be separated because reasoning is needed to understand mathematics and reasoning can be trained through learning mathematics. The purpose of this study was to determine the mathematical reasoning abilities of junior high school students on a two-variable system of linear equations (SPLDV) material with the use of emergent models as one of heuristic in PMRI (Indonesia Realistic Mathematics Education). The subjects in this study were 6 students of class VIII.2 SMP Negeri 17 Palembang. This research is qualitative research. Data collection techniques are carried out through tests, and interviews. Based on the results of trials, overall from the results of the students' answers to each indicator has appeared in its completion. However, students still experience some minor errors, such as in indicator 1 and indicator 3, some students use tables to solve them, but students are wrong in inputting their scores into the table so that the results obtained by students are not correct. However, after tracing from the interview, it was concluded that the cause of the error was because students were confused with the instructions contained in the student worksheets (LKPD). So that the problems that students experience show that students are less careful in presenting mathematical statements, performing mathematical manipulations, and drawing overall conclusions.