Question

What is the interior angle of a regular 21-gon? (Round to 2 decimal places.)

Answer 1

The interior angle of a regular 21-gon is around `162.86^@`.

Explanation:

The sum of interior angles in a polygon with n corners is

`180(n-2)`

A 21-gon therefore has an interior angle sum of:

`180(21-2)=180*19=3420^@`

In a regular 21-gon, all interior angles are equal, so we can find out the measure of one of these angles by dividing `3420` by `21`:

`3420/21~~162.86`