Step-by-step explanation:
the distance is easy. this is just the sum of the distances of the individual trips :
400 + 700 + 1200 = 2300 km
the displacement is trickier. this is the line of sight distance between the starting point of the first trip and the ending point of the last trip.
let's imagine a coordination grid with 1 km as unit size, and the starting point being the origin (0, 0).
so, then the trips subtract 400 units from y, then 700 units from x, and then further 1200 units from y.
so, the coordinates of the end point are (-700, -1600).
the displacement (straight distance from the origin) is then found by using Pythagoras
c² = a² + b² (c being the Hypotenuse, a and b the legs)
via the right-angled triangle of the coordinate differences to the origin :
displacement² = (-700)² + (-1600)² =
= 490000 + 2560000 =
= 3050000
displacement = sqrt(3050000) = 1,746.42492... km