Answer:
∠ D = 110°
Explanation:
Assuming the quadrilateral is a parallelogram.
• Consecutive angles sum to 180° , then
∠ B + ∠ C = 180 , that is
5x + 3x + 4 = 180
8x + 4 = 180 ( subtract 4 from both sides )
8x = 176 ( divide both sides by 8 )
x = 22
Then
∠ B = 5x = 5 × 22 = 110°
• Opposite angles are congruent
∠ D = ∠ B = 110°