Download Polygons--

Polygons---Terms
Geometry (Holt 6-1)
K. Santos
Polygon
Polygon—enclosed figure
--has at least 3 sides (segments)
--sides only intersect at their endpoints
--no adjacent sides are collinear
--poly (many) gon (sides)
Examples on Non-polygons
Parts of a Polygon
Angles
A
<A, <B, <C, <D, <E, <F
Vertices (1—Vertex)--corners
A, B, C, D, E, F
Sides (segments)
𝐴𝐵, 𝐵𝐶, 𝐶𝐷, 𝐷𝐸, 𝐸𝐹, 𝐹𝐴
B
F
Specific Name:
(must list clockwise or counterclockwise)
ABCDEF
DEFABC
EDCBAF
C
E
D
Diagonals
A segment that connects two
nonconsecutive vertices.
A
Diagonals:
𝐴𝐶 𝐵𝐷 𝐶𝐸
𝐴𝐷 𝐵𝐸 𝐶𝐹
𝐴𝐸 𝐵𝐹
𝐷𝐹
B
F
C
E
D
Convex vs Concave
Extend the sides of the polygon to figure out if a figure is convex
or concave.
If all the extensions stay outside of the polygon then it is
convex.
If any of the extensions go into the polygon then it is concave.
concave
Equiangular/Equilateral/Regular
Equiangular—all equal/congruent angles
Equilateral—all equal/congruent sides
Regular polygon—both equiangular and
equilateral
Regular vs irregular polygon
Regular Polygons
Irregular Polygons
Classifying polygon based on number
of Sides
Number of Sides
3
4
5
6
7
8
9
10
11
12
13
n
Name of polygon
triangle
quadrilateral
pentagon
hexagon
septagon/heptagon
octagon
nonagon
decagon
undecagon
dodecagon
13-gon
n-gon