Answer:
We used SSS rule of congruence to prove that the triangles are congruent.
Explanation:
We are given the following information in the question:
AB = CD
BC = DA
We have to prove that
![\angle B = \angle D](https://img.qammunity.org/2020/formulas/mathematics/middle-school/bippu0hmog6adaidceae9h7xh80zbczid0.png)
We will first prove the congruency of triangle.
![\text{In }\triangle ABC \text{ and } \triangle CDA](https://img.qammunity.org/2020/formulas/mathematics/middle-school/l0a4rm1lw06x5fxp7l54qfsfkleqqkif4p.png)
AB = CD ( Given )
BC = DA ( Given )
AC = CA (Common )
Hence,
by SSS rule of congruence( Side Side Side).
Since the triangles are congruent,
![\angle ABC = \angle CDA](https://img.qammunity.org/2020/formulas/mathematics/middle-school/8zmnh0bftx775lwyql7fcu5ox0v8rhrv7t.png)