Polygons Quadrilateral Triangles Pentagon Polygon Song Heptagon Hexagon Decagon Octagon

Definition of Polygon A number of coplanar (on the same plane) line segments, each connected end to end to form a closed shape. Where do we find polygons in nature?

Triangles A triangle is a closed polygon with three segments that are linked end-to-end

Scalene Triangle A triangle where all three sides are different in length

Isosceles Triangle A triangle which has two sides equal in length

Right Triangle A triangle where one of its interior angles is a right angle (90⁰ angle)

Equilateral Triangle A triangle which has all three of its sides equal in length

Quadrilaterals For coplanar (on the same plane) line segments linked end to end to create a closed figure. Also a four-sided polygon

Square A four sided polygon with all sides equal and all internal angles 90⁰

Rectangle A four sided polygon where all interior angles are 90⁰ What is the difference between a rectangle and a square? A square has equal lengths while a rectangle does not

Rhombus A quadrilateral with all four sides equal in length Is a square a rhombus? Why? A square has four sides equal in length it is different because it has equal angles but it is a rhombus

Pentagon A polygon with 5 sides Pentagons are found in soccer balls, also the famous building in Washington D.C

Hexagon A polygon with 6 sides Hexagons are found in bee hives

Heptagon A polygon with 7 sides

Octagon A polygon with 8 sides

Decagon A polygon with 10 sides

Polygon Song Polygons are on a plane Simple, closed, with many a name Line segments for every side Nothing curved can we abide “3” sided are Triangles “4” sided we call Quadrilateral “5” is known as a Pentagon Just like the building in Washington Chorus Think “X” for “6” and Hexagon Cool is “7” Heptagon Octagons have sides of eight Look like stop signs, not home plate Chorus “9” is for a Nonagon Don’t really use then except in song “10” sides make a Decagon Now we know our Polygons! Chorus: Don’t use: 1, 2 Start with: 3, 4 Keep going: 5, 6, 7, 8

Nonagon A nine sided polygon We don’t use nonagons often so we don’t need to know them for this class