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Polygons

  • define polygon and recognize simple, convex and concave;
  • name polygons and recognize regular ones;
  • calculate the number of diagonals and the sum of internal and external angles.

Egyptians and Mesopotamians used polygons to measure land, build monuments and even in religious symbols. Euclid and Archimedes studied its properties in depth. Today they are in crystals, molecules, architecture and computer graphics, in which 3D models are assembled with thousands of small polygons.

Polygons in Mesopotamian buildings.
Polygons in Mesopotamian buildings.
Archimedes used polygons to estimate the number π (chapter 17).
Archimedes used polygons to estimate the number π (chapter 17).
Crystals have polygonal faces.
Crystals have polygonal faces.
Hexagonal rings in molecules.
Hexagonal rings in molecules.
3D games are made of polygon meshes.
3D games are made of polygon meshes.
Polygons and lattices even appear in cryptography.
Polygons and lattices even appear in cryptography.