To determine the order of the side lengths of triangle \( \triangle RST \) based on the given angle measures, we can use the fact that in a triangle, the side opposite the largest angle is the longest and the side opposite the smallest angle is the shortest.
Given the angle measures:
- \( \angle R = 45^\circ \)
- \( \angle T = 105^\circ \)
To find \( \angle S \): \[ \angle S = 180^\circ - \angle R - \angle T = 180^\circ - 45^\circ - 105^\circ = 30^\circ \]
Now we have the angle measures:
- \( \angle R = 45^\circ \) (opposite side \( ST \))
- \( \angle T = 105^\circ \) (opposite side \( RS \))
- \( \angle S = 30^\circ \) (opposite side \( TR \))
Based on these angles:
- \( \angle T \) is the largest angle, so \( RS \) is the longest side.
- \( \angle R \) is the second largest angle, so \( ST \) is the second longest side.
- \( \angle S \) is the smallest angle, so \( TR \) is the shortest side.
Thus, the order of the sides in decreasing order of length is: \[ RS > ST > TR \]
The correct response is: RS > ST > TR.