Regular polygon has all sides equal in length and all angles equal in size.
The sum of interior angles of n sided polygon is
s = (n - 2) x 180°
Problem 1 :
For the following regular polygon given below,
a) Equilateral triangle b) Square c) Pentagon |
d) Hexagon e) Octagon f) Decagon |
find
(i) Number of sides that the polygon has
(ii) Number of angles
(iii) Size of each angle.
Solution :
a) Equilateral triangle
Number of sides = 3, number of angles = 3
b) Square
Number of sides = 4, number of angles = 4
c) Pentagon
Number of sides = 5, number of angles = 5
d) Hexagon
Number of sides = 5, number of angles = 5
e) Octagon
Number of sides = 8, number of angles = 8
f) Decagon
Number of sides = 10, number of angles = 10
Problem 2 :
Find the size of each angle of a regular 12 sided polygon.
Solution :
Sum of interior angles of 12 sided polygon = (12 - 2) x 180
= 10 x 180
= 1800
Each angle measure = 1800/12
= 150
So, the size of each angle of a 12 sided regular polygon is 150 degree.
Problem 3 :
Each exterior angle of a regular polygon is 20⁰. Work out the number of sides of the polygon.
Solution :
Exterior angle of a regular polygon = 20
Interior angle = 180 - 20
Each interior angle = 160
So, the polygon will have 18 sides.
May 21, 24 08:51 PM
May 21, 24 08:51 AM
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