1) [tex]\overline{AB} \perp \overline{BD}[/tex], [tex]\overline{AB} \cong \overline{DB}[/tex], [tex]\overline{AC} \cong \overline{DE}[/tex] (given)
2) [tex]\angle ACB[/tex] is a right angle (perpendicular lines form right angles)
3) [tex]\triangle ABC[/tex] and [tex]\triangle BED[/tex] are right triangles (a triangle with a right angle is a right triangle)
4) [tex]\therefore \triangle ACB \cong \triangle DEB[/tex] (HL)
5) [tex]\therefore \angle ACB \cong \angle DEB[/tex] (CPCTC)
