Polygons – Polygon basics – In Depth
The word polygon
is a combination of two Greek words: “poly” means many and “gon”
means angle. Along with its angles, a polygon also has sides and vertices.
“Tri” means “three,” so the simplest polygon is called
the triangle, because it has three angles. It also has three sides and three
vertices. A triangle is always coplanar, which is not true of many of the
other polygons.
A regular polygon
is a polygon with all angles and all sides congruent, or equal. Here are some
regular polygons.
We can use a
formula to find the sum of the interior angles of any polygon. In this formula,
the letter n stands for the number of sides, or angles, that the polygon has.
sum
of angles = (n 2)180°
Let’s use the
formula to find the sum of