Answer:
10.88 km
Explanation:
We shall represent displacement in terms of i , j unit vectors in the direction of east and north .
4.5 km due west
D₁ = - 4.5 i
6.7 km at an angle of 27° south of west
D₂ = - 6.7 cos27 i - 6.7 sin27j
= - 6.7 x .89 i - 6.7 x .45 j
= - 5.96i - 3 j
Total displacement
= D₁ + D₂
= - 4.5 i - 5.96i - 3 j
= -10.46 i - 3j
Magnitude = √ ( 10.46² + 3²)
= √ ( 109.41 + 9)
= √ 118.41
= 10.88 km .