Question

These triangles are congruent by the triangle congruence postulate [?]

Answer 1

Given:

A figure of two congruent triangles.

To find:

The triangle congruence postulate by which the given triangles are congruent.

Solution:

First label the vertices as shown below.

In triangle ABC and triangle CDA,

`AB\cong CD` (Given)

`\angle BAC\cong \angle DCA` (Given)

`AC\cong AC` (Common side)

The corresponding two sides and their included angle are congruent in both triangles. So, triangles are congruent by SAS congruence postulate.

`\Delta ABC\cong \Delta CDA` [SAS congruence postulate]

Therefore, the correct option is B.