Answer:
1. [tex]\angle B \cong \angle D[/tex] 1. Given.
2. [tex]\angle DAE \cong \angle BEA[/tex] 2. Given.
3. [tex]\triangle AEC[/tex] is isosceles 3. by statement 2 and definition of triangle isosceles.
4. [tex]AC \cong EC[/tex] 4. by definition of triangle isosceles.
5. [tex]\angle ACB \cong \angle ECD[/tex] 5. by vertical angles.
6.
[tex]\angle B + \angle ACB + \angle BAC = 180\°\\\angle D + \angle ECD + \angle DEC = 180\°[/tex] 6. by internal angles of a triangle.
7. [tex]\angle B + \angle ACB + \angle BAC =\angle D + \angle ECD + \angle DEC \\\angle BAC = \angle DEC[/tex] 7. by statement 1, 5 and 6.
8. [tex]\triangle ABC \cong EDC[/tex]. 8. by AAA postulate.
Remember, the AAA postulate is about the congruence between thre pairs of corresponding angles.
