From Congruent Angles to Congruent Trıangles: The Role of Dragging, Grid and Angle Tools of A Dynamic Geometry System

This study aims to establish a conceptual relationship between the angles of two parallel lines intersected by a transversal and the congruent triangles formed through the points on the parallel lines and the transversal. At this point, the study considers semiotic potential of dragging, grid and angle tools of a dynamic geometry system. The study was designed according to qualitative paradigm, and the collected data was analyzed through the techniques used in the same perspective. Within the scope of the study, an instructional task was designed by employing the tools used in a dynamic geometry system and its functions. This task was expected to enable the participants to make a successful conceptual bridging by using their already existing background knowledge. In addition, two sessions of 25-minute clinical interviews were conducted with two students – one from 7th and one from 8th grade – who were selected according to the principles of purposeful sampling method. The findings obtained from qualitative data analysis show that the designed task can be used as a tool for students to figure out conceptual relationships between congruent angles and congruent triangles. The results clearly revealed that the students went through different cognitive processes while using the dragging tool. Generally speaking, the findings are consistent with the findings of similar studies in the literature, and some suggestions were proposed under the light of these findings

Keywords:

Congruent Angles, Congruent Triangles Dynamic Geometry System, Semiotic Potential,

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