Answer:
The answer is given below
Explanation:
Statement Reason
Triangle ACD is isosceles Given
<1 = <3 Given that <1 is congruent to <3
∠3 = ∠4 Base angles of an isosceles
. triangle is equal
∠1 = ∠4 By substitution, since ∠1 = ∠3
. and ∠3 = ∠4, therefore ∠1 = ∠4
Segment AB || Segment CD Alternate interior angle theorem . Since ∠1 = ∠4 (alternate
, interior angles)
Alternate interior angle theorem states that if two lines and a transversal line form alternate interior angles that are equal, then the two lines are parallel to each other.
AB and CD and transversal AD form alternate interior angles (∠1 and ∠4), therefore AB and CD are parallel