Answer :
156°
Explanation :
Each triangle has an angle sum of 180 degrees.
The sum of the interior angles of the 15 sided polygon =
(n-2)180°
(n-2)180°
(15-2) × 180°
13 × 180 = 2340 °
Since the 15 sided polygon is regular, this total is shared equally among the 15 interior angles. Each interior angle must have a measure of
2340° ÷ 15 = 156 °each