Final answer:
Since QS is the median of triangle PQR, it divides PR into two equal segments. Therefore, PS is congruent to SR.
Step-by-step explanation:
Given QS is the median of triangle PQR, QS is a line segment that joins vertex Q to midpoint S of PR. By definition of median in a triangle, the median divides the base (in this case, PR) into two equal parts.
Therefore, the length of the line segment PS equals to the length of line segment SR. In other words, you can say PS is congruent to SR. This is because the definition of a median states that it divides the base of a triangle into two segments of equal length.
Learn more about Median of a Triangle