Number of sides of an n-sided regular polygon
If the interior angle of a regular polygon is x° and the number of sides is 'n', then =
| Each interior angle |
= |  |
| x | = |  |
| nx | = | 180n – 360 |
| 360 | = | 180n – nx |
| 360 | = | n(180 – x) |
| n | = |  |
If the sum of interior angles of a regular polygon is s, and the number of sides is 'n', then
| (n – 2) × 180 | = s |
| n – 2 | =  |
 n |
=  + 2 =  |
Q
The interior angle of a 15 sided regular polygon is of measure?
Sol:
Interior angle of a 15 sided regular polygon
