Question

which angle is vertical to ∠bfc?

Explanation:

Step1: Recall vertical - angle definition

Vertical angles are formed when two lines intersect. They are opposite each other and are congruent.

Step2: Identify intersecting lines and vertical angles

Lines $BC$ and $ED$ intersect at point $F$. $\angle BFC$ and $\angle DFE$ are opposite each other at the intersection of these two lines.

Answer:

$\angle DFE$