<u>Part</u><u> </u><u>(</u><u>i</u><u>)</u>
1. ABCD is a quadrilateral in which AD=BC and ∠DAB=∠CBA (given)
2. AB = AB (reflexive property)
3. Triangles ABD and BAC are congruent (SAS)
<u>Part</u><u> </u><u>(</u><u>ii</u><u>)</u>
4. BD=AC (corresponding sides of congruent triangles are equal)
<u>Part</u><u> </u><u>(</u><u>iii</u><u>)</u>
5. ∠ABD = ∠BAC (corresponding angles of congruent triangles are equal)