1) [tex]\triangle ABC[/tex] with [tex]\overline{AC} \cong \overline{BC}[/tex], [tex]\overline{AB} \parallel \vec{CE}[/tex] (given)
2) [tex]\angle A \cong \angle B[/tex] (base angles theorem)
3) [tex]\angle A \cong \angle 1[/tex] (corresponding angles theorem)
4) [tex]\angle B \cong \angle 2[/tex] (alternate interior angles theorem)
5) [tex]\angle 1 \cong \angle 2[/tex] (transitive property of congruence)
6) [tex]\vec{CE}[/tex] bisects [tex]\angle BCD[/tex] (if a ray splits an angle into two congruent parts, it is a bisector)
