I believe the matching would be as follows; 1. ABCD is a rhombus -Given 2. Triangle ADB congruent to Triangle CDB- Diagonals of parallelogram make congruent triangles. The two triangles share a diagonal BD as their third side. 3. ∠1=∠2, ∠3=∠4 ; CPCTE 4. DB bisects ∠ABC and ∠ADC - definition of angle bisector