YUMNIYATI, K. .-.; SUJADI, I. .-.; INDRIATI, D. .-. COGNITIVE LEVEL PROFILE AT THE TENTH GRADE OF SENIOR HIGH SCHOOL STUDENTS IN MATHEMATICS PROBLEM SOLVING ON THREE VARIABLES OF LINEAR EQUATION SYSTEM. International Online Journal of Education and Teaching, [S. l.], v. 6, n. 3, p. 473–485, 2019. Disponível em: https://iojet.org/index.php/IOJET/article/view/535. Acesso em: 8 jan. 2026.