To prove quadrilateral wxyz is a parallelogram, travis begins by proving △wzy ≅ △yxw by using the sas congruency theorem. which reasons can travis use to prove the two triangles are congruent? check all that apply. ∠zwy ≅ ∠xyw by the alternate interior ∠s theorem. wy ≅ wy by the reflexive property. ∠zwy ≅ ∠xwy by the corresponding ∠s theorem. wx ≅ zy by definition of a parallelogram. wz ≅ xy by the given.