In the figure BC || DE . Angles_
CAF and EFA
GAC and DFE
CAF and EFH
GAB and EFA
are congruent_
By linear pair theorem
because they are corresponding angles of parallel lines cut by a transversal
by vertical angles theorem
by the transistive property of congruence

∠GAC ≅ ∠AFE because they are corresponding angles of parallel lines cut by a transversal. ∠AFE ≅ ∠HFD by the Vertical Angles Theorem. ∠GAC ≅ ∠HFD by the_ Property of Congruence.
addition
subtraction
substitution
transistive