Given:
The sum of the speeds of two trains is 721.4
Let the speed of the trains are x and y
So,
[tex]x+y=721.4\rightarrow(1)[/tex]And the speed of the first train is 4.6 mph faster than the second train
So,
[tex]x-y=4.6\rightarrow(2)[/tex]Solve the equations (1) and (2) to find x and y
Add the equations to eliminate (y) then solve for (x):
[tex]\begin{gathered} 2x=721.4+4.6 \\ 2x=726 \\ x=\frac{726}{2}=363 \end{gathered}[/tex]Substitute (x) into the first equation then solve for (y):
[tex]\begin{gathered} 363+y=721.4 \\ y=721.4-363=358.4 \end{gathered}[/tex]So, the answer will be:
The speeds of the trains are 363 mph and 358.4 mph