Analysis of Critical Thinking Ability in Solving Linear Programming Problems in terms of Students' Self-Concepts

The complex internal process of learning is very closely related to thinking because complex activities and closely related to one another is a way of thinking to solve problems and produce something. This article aims to analyze critical thinking skills in solving linear program questions in terms of students' self-concept. This type of research is qualitative research with a case study method. The research subjects were five students of IPA vocational high school. The instruments used were tests, interviews, and questionnaires. The results showed that students with high self-concept, the ability to think critically in solving linear program questions were still low, the low ability to think critically of students in solving questions was still a lot of errors including: (1) Writing incorrect, incorrect and unsystematic concepts, (2) The picture is incomplete, (3) on the student's answer sheet, (4) write down the reasons for the arguments that are still unclear, while the results of the interview show the students can verbally convey answers in solving linear program problems.