Question

which angle is complementary to ∠cfd?

Explanation:

Step1: Recall complementary - angle definition

Two angles are complementary if their sum is 90 degrees. Since there is a right - angle at F (indicated by the small square), angles that make up this right - angle with ∠CFD are its complementary angles.

Step2: Identify the complementary angle

From the figure, ∠DFE and ∠CFD together form a right - angle. So, ∠DFE is complementary to ∠CFD.

Answer:

∠DFE