a polygon is any shape with at least 3 straight sides and angles.
-triangle, 3 sides
-square, 4 sides
-pentagon, 5 sides
-hexagon, 6 sides
-heptagon, 7 sides
-octagon, 8 sides
-nonagon, 9 sides
-decagon, 10 sides
here are two more:
-parallelogram, 4 sides
-rectangle, 4 sides
