Hi,
Departure point : (4, 5)
They are first heading west, to go to the (2,5). They made 2 km.
Then they are heading north, to go to (2,8) -> campsite. They made 3 km
To return to departure point, the make the choice to walk in straight line :
[tex]d = \sqrt{(4 - 2)^{2} + (5 - 8)^{2}} \\ \\ d = \sqrt{4 + 9} \\ \\ d = \sqrt{13} \\ \\d \approx 3.60\;km[/tex]
In total : they walked : 2 + 3 + 3.60 = 8.60 km
