and are three vertices of a polygon as shown above. The reflex angle and the size of the remaining exterior angles are equal to each. Calculate the number of sides this polygon has.
To calculate the total angle of all the interior angles added, we use:
a = sum of total internal angles
n = number of sides
Now given the information:
- One internal angle is 138 degrees
- The rest of the internal angles are 127 degrees
Therefore, the total internal angle can be calculated by:
Now use simultaneous equation to solve for n.