Step-by-step explanation:
the sum of the interior angles of a polygon (a closed object with n edges) is always (n-2)×180°.
we have here 5 edges, so the sum of all 5 angles is
(5-2)×180 = 3×180 = 540°.
now, let's simply calculate
5x + 2 + 7x - 11 + 13x - 31 + 8x - 19 + 10x - 3 = 540
43x - 62 = 540
43x = 602
x = 14
therefore,
angle S = 13x - 31 = 13×14 - 31 = 182 - 31= 151°
