Pentagon Geometry

thingiverse

My partner and I, Kevin Miller, crafted this design side by side in Dan Jackson's college geometry class. It is a pentagon with one wall extended, surrounded by five 90-degree triangles inside. If you sum up the acute angles of the five triangles, adding four together plus the adjacent one left intact will total 90 degrees, equalling 18 times 5. We developed this design from a homework problem requiring us to prove that if all five walls of the pentagon are extended, the resulting exterior angles will equal four right angles.