<![CDATA[Mathematical reasoning ability is an ability that is considered important for students to have in learning mathematics. The purpose of this study is to describe students' mathematical reasoning ability on the material of Two Variable Linear Equation System . This type of research is a type of research that uses a descriptive method with a qualitative approach. Data collection techniques in this study were carried out using observation, test, and interview methods. The test instrument used was 2 essay questions about students' reasoning ability that had been validated. The subjects of this study were 20 students of class VIII 1 SMP Negeri 4 Koto Gasib. Based on the test results, the researcher selected students who had the same ability, then 6 students were selected as representatives of the research subjects based on the category (high, medium and low). The results of this study indicate that students with high initial ability are able to meet all indicators of mathematical reasoning ability. Students with medium ability are not yet able to present mathematical statements in writing, are able to submit conjectures but the steps are not complete, are able to manipulate well, are able to compile evidence of the truth of the solution and are able to draw conclusions correctly and precisely. Students with low abilities are unable to present mathematical statements in writing, are able to submit conjectures but the steps are incomplete, are able to manipulate correctly, but are not yet able to compile evidence for the truth of the solution and finally students are unable to draw conclusions from the answers they have obtained.]]>
