After some calculations, you would realize that repeating division one time and another is long and tedious. Use this model instead to validate your conjecture related to the previous explorative model. Spreadsheets make divisions easier, any time you insert values correctly![br][br]Students work in pairs (two student, A and B).[br][br]1) Student A introduces a numerical value for the the acute angle ([math]\alpha[/math]) in the dynamic, and this value remains unchanged until step (5). Then, student A drags the orange point to modify the base-length of the triangle.[br]2) Student B translates values of the triangle from the model to the spreadsheet and performs calculations in the spreadsheet with the given information.[br]3) Students switch positions. Student B decides a new position for the orange point (without changing the angle, since the “input box” is gone for the moment), and student A performs new calculations. Students repeat steps 2 and 3 a number of times.[br]4) Students must formulate a conjecture and the conjecture must be coherent with the obtained data.[br]5) Students push the “new angle” button, and they start again from step 1 with a new triangle.[br]6) After repeating the process with a number of triangles, students reformulate their conjecture, which must be coherent with the obtained new data.