The concept of congruence is an important one in geometry, and understanding which triangles can be proven congruent is essential for any student of mathematics. Congruent triangles are triangles that have the same size and shape; in other words, they have the same angles and the same side lengths. The Side-Angle-Side (SAS) postulate states that if two sides and the included angle of one triangle are congruent to two sides and the included angle of another triangle, then the two triangles are congruent. In this article, we will explore how to identify congruent triangles and apply the SAS postulate to determine which pairs of triangles can be proven congruent.

## Identifying Congruent Triangles

The first step to determining which pairs of triangles can be proven congruent by SAS is to identify which triangles are actually congruent. To do this, first examine the sides and angles of the two triangles to see if they are equal in size and shape. If the sides and angles are the same, then the triangles are congruent. Additionally, if two sides and the included angle of one triangle are congruent to two sides and the included angle of another triangle, then the triangles are also congruent.

## Applying the SAS Postulate

Once the congruent triangles have been identified, the SAS postulate can be applied. This postulate states that if two sides and the included angle of one triangle are congruent to two sides and the included angle of another triangle, then the two triangles are congruent. Thus, if two triangles are found to have two sides and the included angle congruent to each other, then they can be proven congruent using the SAS postulate.

In conclusion, the SAS postulate states that if two sides and the included angle of one triangle are congruent to two sides and the included angle of another triangle, then the two triangles are congruent. Identifying congruent triangles is the first step to applying the SAS postulate, and the postulate can then be used to prove that two triangles are congruent. With this knowledge, students of mathematics can more easily determine which pairs of triangles can be proven congruent using the SAS postulate.