REFLECTIVE TEACHING DESIGN AND CASE ANALYSIS OF MATHEMATICS PROPOSITION COURSE IN MIDDLE SCHOOL—TAKE THE DECISION OF CONGRUENT TRIANGLE AS AN EXAMPLE . J. Song. Math [Internet]. 2023 Aug. 12 [cited 2026 Jul. 30];6(1):12-9. Available from: https://jurnal.unikastpaulus.ac.id/index.php/JSM/article/view/1669