Answer:
∠DEB = 85°
Step-by-step explanation:
Vertical Angle Theorem
When two straight lines intersect, they form two pairs of angles. The vertically opposite (non-adjacent) angles are congruent.
Angles AEC and DEB are vertically opposite angles, therefore:
∠AEC = ∠DEB
As ∠AEC = 85° then ∠DEB = 85° also.
