Trịnh Thị, L.M. 2026. TEACHERS’ DIFFICULTIES IN THE EXPLOITATION AND REINFORCEMENT OF MATHEMATICAL ACTIVITIES FOR STUDENTS IN TEACHING ALGEBRA 10: A PRACTICAL STUDY AT SELECTED HIGH SCHOOLS IN THE PROVINCE. Hong Duc University Journal of Science – Educational Science and Management. 85, 3 (Mar. 2026). DOI:https://doi.org/10.70117/hdujs.85.3.2026.1007.