Answer:
Her displacement is 10km
Explanation:
An illustrative diagram for the journey is shown in the attachment below.
From the question,
She travels north 5km, which is given by /AB/ in the diagram, and 10km west, which is given by /BC/ in the diagram. She then travels 5km south, which is given by /CD/ in the diagram. To determine her displacement,
Displacement is the shortest distance from an initial position to a final position.
Therefore, her displacement is given by /DA/ in the diagram.
NOTE: /DA/ = /BC/ (Opposite sides of a rectangle)
Since /BC/ = 10km
∴ /DA/ = 10km
Hence, her displacement is 10km.
