\(\Rightarrow\left\{{}\begin{matrix}0,5\left(v1+v2\right)=60\\2\left(v1-v2\right)=60\end{matrix}\right.\left(v1>v2\right)\)
\(\Leftrightarrow\left\{{}\begin{matrix}v1+v2=120\\v1-v2=30\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}v1=75\\v2=45\end{matrix}\right.\left(km/h\right)\)