Answer
$\angle$ FAC and $\angle$ CAD form a linear pair.
Work Step by Step
Since ray AF and ray AD are opposite angles, they form a line. And since $\angle$ FAC and $\angle$ CAD are adjacent angles they form a linear pair.
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.