Question

ABDC is an isosceles trapezoid. Given only the choices below, which properties would you use to prove ACD ≅ BDC by SSS?

Answer 1

If the choices are the following:
The legs are congruent.
The base angles are congruent.
The bases are | |.
The diagonals are congruent.
Then , to prove ACD ≅ BDC by SSS I would use The base angles are congruent. 
This is sufficient to prove the triangles are congruent.