Question

Prove that the sum of interior angles of an octagon is twice the sum of the interior angles of a pentagon.​

Answer 1

Answer:

To find the measure of the angles, we know that the sum of all the angles is 1080 degrees (from above)... And there are eight angles... So, the measure of the interior angle of a regular octagon is 135 degrees.

Answer 2

Answer:

sum lf interior angle of any regular polygon can be given by

180(n - 2)180(n−2)

where n is the no. of sides of polygon

for pentagon

n = 5

so sum of all interior angles is

180[5-2]

180(3)

540°

and for octagon

n = 8

so sum of interior angles is

180(8-2)

180(6)

1080° = 2(540)..