Siahaan, M., Situmorang, A. S., Sinaga, S. J., & Manullang, D. T. (2023). Efektivitas Model Problem Based Learning Terhadap Kemampuan Representasi Siswa Kelas VIII Materi Sistem Persamaan Linier Dua Variabel SMP Negeri 15 Medan. Innovative: Journal Of Social Science Research, 3(2), 433–450. Retrieved from https://j-innovative.org/index.php/Innovative/article/view/349