Answer:
∠DEC or ∠AEB
Explanation:
An adjacent angle is one that shares a side and a vertex, but no interior space.
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Angle DEA has its vertex at point E, and has sides ED and EA.
Another angle with side ED and vertex E is angle DEC.
Another angle with side EA and vertex E is angle AEB.
Angles adjacent to angle DEA are DEC and AEB.