To use the SAS (Side-Angle-Side) Congruence Theorem to prove that triangle \( \triangle ABC \) is congruent to triangle \( \triangle ADC \), Leah needs to establish the following:
- Side: \( AB \cong AD \) (This is given.)
- Included Angle: \( \angle BAC \cong \angle DAC \) (This is true because line \( AC \) is the angle bisector of \( \angle BAD \).)
- Side: \( BC \cong DC \) (This follows from the properties of the kite, as the two triangles share side \( AC \), which is congruent to itself.)
With these details in mind, the best option is:
Option #2: \( AB \cong AD \), \( \angle BAC \cong \angle DAC \), \( BC \cong DC \)
This option correctly lists the sides and angles necessary to apply the SAS Congruence Theorem to show \( \triangle ABC \cong \triangle ADC \).