Answer:
∠ S = 151°
Explanation:
The sum of the interior angles of a polygon is
sum = 180° ( n - 2) ← n is the number of sides
Here n = 5, thus
sum = 180° × 3 = 540
Sum the interior angles and equate to 540
10x - 3 + 5x + 2 + 7x - 11 + 13x - 31 + 8x - 19 = 540, that is
43x - 62 = 540 ( add 62 to both sides )
43x = 602 ( divide both sides by 43 )
x = 14
Thus
∠ S = 13x - 31 = 13(14) - 31 = 182 - 31 = 151°