Pearl is preparing a proof for the Converse of the Triangle Proportionality Theorem using the image above. She knows that AD over AB equals AE over AC:


Statement Reason
1 AD over AB equals AE over AC Given
2 ∡A ≅ ∡A Reflexive Property
3 ΔDAE ~ ΔBAC Side-Angle-Side (SAS) Similarity Postulate
4 ∡ADA ≅ ∡ABC Corresponding Angles of Similar Triangles are Congruent
5 DE || BC Converse of Corresponding Angles Postulate


In which step is her first mistake?