Brief introduction about Polygons

1. POLYGONS

2.  Most of the basic shapes, such as triangle, square,
rectangle, are parts of a larger subset of closed
figures bounded by broken lines called polygons.
 The term “polygon” is a combination of two Greek
words, “poly” which means “many” and “gonia”
which means “angle”.
 POLYGON
- is a two-dimensional closed figure bounded by
straight line segments.

3. 1. Side or edge
- is one side of the line segments that make up the
polygon.
2. Vertex
- is a point where the sides meet.
3. Diagonal
- is a line connecting two non-adjacent vertices.

4. 4. Interior angle
- is the angle formed by two adjacent sides inside the
polygon.
5. Exterior angle
- is the angle formed by two adjacent sides outside the
polygon.
6. Apothem (of a regular polygon)
- is the segment connecting the center of a polygon and
the midpoint of a side. The apothem is also a perpendicular
bisector of the side.
7. Central angle (of a regular polygon)
- is the angle subtended by a side about the center.

6. a.
b.
c.
Figure 2.2
 Typical polygons are
illustrated in Figure 2.2-a.
 Although figure 2.2-b is
bounded by straight lines, it
is not a polygon since it is
not a closed figure.
 The closed Figures in 2.2-c
are non polygons since they
are enclosed by curves.

7.  Three major conditions are needed to classify a
polygon.
◦ First, it must be a two-dimensional figure.
◦ Second, a polygon must be a closed figure.
◦ Lastly, it should be bounded by straight lines
Polygons are said to be similar if their corresponding
interior angles are equal and their corresponding sides
are proportional.

8.  By ratio and proportion, we obtain the following equations
from two similar polygons.
a)
where x1 and x2 are any two sides of a polygon and y1 and
y2 are the corresponding sides of a similar polygon.
b) 2
where A1 and A2 are the areas of the two similar polygons
with x and y as their corresponding sides respectively.

9.  RADIN Types of polygons.pptx
 FORMULAS molate.pptx