Megan's commute to work includes an 8-mile drive and a 21-mile train ride. This expression can be used to find the total time it takes Megan toget to work, where x is her average driving speed in miles/hour.

The time is:
[tex]time=\frac{distance}{average\text{ }speed}[/tex]Then, the average speed of the train is represented by x + 20.
If x = 45, then:
[tex]\begin{gathered} time=\frac{8}{45}+\frac{21}{45+20} \\ time=0.5\text{ }hour \end{gathered}[/tex]Answer:
1) x + 20
2) 0.5 hour