Q:

the measure of the seven angles in a nonagon measure 138, 154, 145, 132, 128, 147 and 130. if the two remaining angles are equal in measure, what is the measure of each angle

Accepted Solution

A:
A polygon is any figure sided with three sides and above such that triangle (3) is the smallest polygon. A nonagon is a polygon with 9 sides. To get the sum of interior angles of a polygon we use the formula;
(n-2) 180 or (n-4)90 where n is the number of sides.
Therefore, for a nonagon the sum of interior angles = (9-2) 180 = 1260 degrees
If we add all the angles we should get 1260, considering the remaining angles to be each x
Thus 138+154 +145 +132 +128 +147 +130 + x +x =1260
                             = 974 + 2x = 1260
                             = 2x = 286
                             = 143
 therefore, each of the other angles was 143