Question

which angles are vertical angles? <dcf and <dca <dca and <gfc <efc and <gfh <gfc and <bcf

Explanation:

Step1: Recall vertical - angles definition

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

Step2: Analyze each option

In the given figure, when two lines are intersected by a transversal, vertical - angles are pairs of non - adjacent angles formed by the intersection of the lines. For example, if we consider the intersection of the two lines cut by the transversal, ∠DCF and ∠DCH are not vertical angles. ∠DCH and ∠GFC are corresponding angles. ∠EFC and ∠GFH are vertical angles because they are formed by the intersection of the two lines and are opposite each other. ∠GFC and ∠ACF are alternate interior angles.

Answer:

∠EFC and ∠GFH