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, angles that make up this right - angle with ∠CFD are complementary to it.

Step2: Identify the complementary angle

From the figure, ∠DFE and ∠CFD together form a right - angle at F.

Answer:

∠DFE