polygon and its properties

2. SREE NARAYANA TRAINING COLLEGE
SREEKANDESWARAM , CHERTHALA,
POOCHAKKAL
KERALA UNIVERSITY
B.Ed 2014-2015

3. PAPER IX
THEORETICAL BASES OF
MATHEMATICS EDUCATION II

4. SUBMITTED BY,
NAME : JESNA JOSEPH
OPTION : MATHEMATICS
REG NO : 18014383002

5. SUBMITTED TO,
Mrs. GEETHA . P
Lecturer in Mathematics
S N T C, Poochakkal

6. STANDARD : IX
UNIT : POLYGONS
TOPIC : PROPERTIES OF POLYGONS

7. POLYGONS
A closed geometrical figure formed
by three or more straight lines is called a
polygon.

8. SOME POLYGONS AND THEIR NAMES
TRIANGLE
QUADRILATERAL

9. PENTAGON

10. HEXAGON

11. A polygon with seven sides and angles is called a hectagon.
A polygon with eight sides and angles is called an
Octagon.
A polygon with nine sides and angles is called a Nanagon.

12. ANGLES OF A POLYGON
 The sum of angles of a polygon with ‘n’
sides is ( n-2 ) x 1800
 The sum of exterior angles of a polygon is 3600

13. Consider a polygon with 12 sides.
a) Find the sum of interior angles of the polygon.
b) What about the sum of exterior angles of the polygon.

14. Solution:
No of sides = 12
a) Sum of interior angles = ( n-2 ) x 1800
= ( 12-2 ) x 1800
= 18000
b) Sum of exterior angles = 3600

15. THANK YOU