It seems the first line has to be
1. AB=CD and AD=CB 1. given
2. AC=AC 2. Reflexivity (things are equal to themselves)
3
ACB 
CAD 3. SSS
4.
1 = 4. Corresponding parts of congruent triangles
5 DC || AB 5. Congruent alternate traversal angles imply parallel lines
1. AB=CD and AD=CB 1. given
2. AC=AC 2. Reflexivity (things are equal to themselves)
3
4.
5 DC || AB 5. Congruent alternate traversal angles imply parallel lines
