congruent figures

Let PQRS be a parallelogram and PR be one of its diagonals. What can you say about triangles PQRC andRSP?Solution:Step 1: In a four-sided figure, opposite sides are congruent. Hence sides Step 2: QR and PS are congruent, and also sides PQ and RS are congruent.Step 3: In a four-sided figure opposite angles are congruent. Step 4: Hence angles PQR and RSP are four side figure.Step 5: Two sides and an included angle of triangle PQR are congruent to two corresponding sides and an included angle in triangle RSP. According to the above postulate the two triangles PQR and RSP are congruent.