<em>If one side of a triangle is longer than another side, then the angle opposite the longer side will be larger than the angle opposite the shorter side</em>
The values of the angles are:
∠S= 50°,
∠T= 60°,
∠R= 180°- (50°+60°)= 180° - 110° = 70°
Since ∠R is the largest angle, the side ST is longest