Answer:
x = 140
Explanation:
the sum of the interior angles of a polygon is
sum = 180° (n - 2) ← n is the number of sides
here n = 6 , then
sum = 180° × (6 - 2) = 180° × 4 = 720°
sum the 6 interior angles and equate to 720
x + 90 + 104 + 123 + 155 + 108 = 720
x + 580 = 720 ( subtract 580 from both sides )
x = 140