Answer:
Step-by-step explanation:
1) [tex]\angle AED[/tex] and [tex]\angle BEC[/tex] are vertical angles
2) [tex]\angle AED[/tex] and [tex]\angle BEC[/tex] are created by intersecting lines (definition of vertical angles)
3) [tex]\angle AED[/tex] and [tex]\angle AEB[/tex] form a linear pair, [tex]\angle AEB[/tex] and [tex]\angle BEC[/tex] form a linear pair
4) [tex]\angle AED[/tex] and [tex]\angle AEB[/tex] are supplementary, [tex]\angle AEB[/tex] and [tex]\angle BEC[/tex] are supplementary
5) [tex]\angle AED \cong \angle BEC[/tex]
