Answer:
1.) AB ⊥ BD, AB ⊥ BC, AC = AD --- d.) Given
2.) ∠ABC and ∠ABD are right angles --- c.) Perpendicular Lines Form Right Angles
3.) AB = AB --- a.) Reflexive Property of Equality
4.) △ABC ≅ △ABD --- b.) Hypotenuse - Leg Postulate
Explanation:
1.) AB ⊥ BD, AB ⊥ BC, AC = AD
2.) ∠ABC and ∠ABD are right angles
3.) AB = AB
4.) △ABC ≅ △ABD
a.) Reflexive Property of Equality
b.) Hypotenuse - Leg Postulate
c.) Perpendicular Lines Form Right Angles
d.) Given