If one angle of a triangle has a greater measure than another angle, then the side opposite the greater angle is longer than the side opposite the lesser angle.
Note that this theorem is used to compare the sides of a triangle. Therefore, because RQ and PQ are two sides of △ QPR, we will consider the interior angles of △ QPR. Keeping this information in mind, let's consider the given diagram.
We can see that ∠ QPR is opposite to RQ and ∠ PRQ is opposite to PQ. Because the measure of ∠ PRQ is greater than the measure of ∠ QPR, we know that PQ is longer than RQ.
PQ > RQ
