15 points! Make sure everything is correct!

These all start the same way:

1. AD ≅ CD  Given

2. BD ⊥ AC  Given

ok, now we're aiming for congruent triangles using SAS

3. BD ≅ BD    Reflexive property

4. ∠ADB and ∠CDB are right        Def perpendicular lines

5. ∠ADB ≅ ∠CDB are right        Right angle congruence theorem (!)

6. ΔADB ≅ ΔCDB                       SAS

7. ∠ABD ≅ ∠CBD                      CPCTC

32

step-by-step explanation:

the first one, all those points on the line just make a strait line.