Answer
$\angle ADE\text{ and }\angle EDF\text{ are supplementary.}$
Work Step by Step
$\text{Supplementary}$ angles are two angles whose sum is $180^{\circ}$. Since $\angle ADE\text{ and }\angle EDF$ are adjacent and form a straight ($180°$) angle, they fit this definition, and we can consider them to be $\text{supplementary}$.
