Question

Find the number of sides in a regular polygon, when each interior angle is: 120°

Answer 1

Each interior angle of a regular polygon

= `(("n" - 2) xx 180°)/"n"`

⇒ `(("n" - 2) xx 180°)/"n"` = 120°

⇒ 180°(n - 2) = 120°(n)
⇒ 3(n - 2) = 2n
⇒ n = 6.