Internal angles of a polygon
The triangle has n=3 sides, and the sum of its internal angles is 180°
The rectangle has n=4 sides, and the sumo of its internal angles is 360°
There is a general formula to calculate the sum of the internal angles of any polygon of n sides:
Sum = 180° ( n -2 )
For a pentagon (n=5), the sum of angles is:
Sum = 180° ( 5 -2 ) = 180° * 3 = 540°
We are required to find the measure of each internal angle. Since the pentagon is regular, all of its internal angles measure the same, thus:
The measure of each angle = 540° / 5 = 108°