Question

A B C D E is a regular pentagon , find the following
(i) angle 1 + angle 2 + angle 3 + angle 4 + angle 5
(ii) is angle 1 = angle 2 = angle 3 = angle 4 = angle 5 true ?
(iii) Find the measures of angle 1 , angle 2 , angle 3 , angle 4 and angle 5​

Answer 1

Step-by-step explanation:

Since side of pentagon, x =5

∴ Each interior =

5

2×5−4

×90

o

=108

o

Since ΔCDE is an isosceles triangle

∴2∠CDB=180−108=72

or ∠CDE=36

o

∴∠BDE=108−36

o

=72

o