The use of Excel to explore old, well-known geometrical theorems is set in the context of Napoleon’s Theorem. A number of geometrical ideas are drawn into the investigation, and spreadsheet examples are given to show how Excel can effectively model such concepts. The article concludes with a generalisation with respect to lines drawn from the vertices of a triangle.

The article is not written primarily from the geometrical point of view, but emphasis is placed on the role that spreadsheets can play in developing an environment in which ideas can be explored and discovered by students. The benefits of using Excel in the context of a geometric investigation are outlined in terms of student control and ease of learning of the environment together with the spreadsheet’s ability to cope with exceptions without halting.

DrawingATriangle.doc (37 kB)
File 1

NapoleonandBeyond.xls (101 kB)
File 2