Answer:
∠ CDE = 134°
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° × 4 = 720°
let ∠ BCD = x then ∠ CDE = 2x
sum the angles and equate to 720
121 + 144 + 129 + 125 + x + 2x = 720 , that is
519 + 3x = 720 ( subtract 519 from both sides )
3x = 201 ( divide both sides by 3 )
x = 67
Then
∠ CDE = 2x = 2 × 67 = 134°