Answer:
x = 129
Step-by-step explanation:
Mathematically, the sum of interior angles of a polygon can be calculated using the formula;
(n-2)180
from the question given , n = 7 since the polygon has 7 sides
thus, we have it that
(7-2)180 = 5 * 180 = 900
Mathematically, by adding all the given interior angles, we can get the value of the total
We have this as;
900 = x + 131 + 119 + 125 + 133 + 125+ 138
900 = x + 771
x = 900-771
x = 129
