Technology plays a crucial role in promoting interdisciplinarity between mathematics and physics. It enhances the understanding of complex concepts, makes learning more meaningful, and ultimately broadens the connections between different fields of knowledge. This requires teachers to mobilize pedagogical and disciplinary knowledge to use it effectively. This study analyzes how two mathematics teachers mobilize their knowledge when integrating a physics concept, exploring the relationship between interdisciplinary practice and technological integration. The research is guided by two questions: Q1) What domains of knowledge are mobilized by the two teachers when working on the same mathematical application in an interdisciplinary context using a graphing calculator (GC)? Q2) How is the level of technology integration influenced by the teachers’ professional knowledge? Using a qualitative and interpretive approach, semi-structured interviews were conducted and lessons were observed involving two mathematics teachers integrating graphing calculators into interdisciplinary practices. The results indicate that both demonstrated interdisciplinary knowledge, but with different approaches to the use of GC. It is concluded that the depth of technological integration is directly related to each teacher’s mastery of interdisciplinary and pedagogical knowledge.