Refer to the image attached.
Given: AB ∥ DE
To Prove:
Statements
1. AB ∥ DE
Reason: Given
2.ACB and ECD are vertical angles.
Reason: Definition of vertical angles
3.
Reason: vertical angles are congruent
4. are alternate interior angles.
Reason: Definition of alternate interior angles
5.
Reason: Alternate interior angles are congruent
6.
Reason: By AA criteria
AA criteria for similarity states that "If two angles of one triangle are respectively equal to two angles of another triangle, then the two triangles are similar".
Therefore,