The measure of all angles is congruent in both triangles.
Based on the image, the side RP is similar to US. Then, we can build the following relationship
[tex]\frac{57}{95}=\frac{x}{78}[/tex]
where x is the side we want to know. Solving for x:
[tex]x=\frac{57}{95}\cdot78[/tex][tex]x=\frac{4446}{95}[/tex][tex]x=46.8[/tex]
Answer: 46.8
