Final answer:
The total displacement of a person can be determined using vector addition, breaking the journey down into its directional components. The 45° angle mentioned is likely a reference to the directional components of a southeast vector.
Step-by-step explanation:
To find the total displacement made by the person, we can use vector addition. The displacement vector for the initial 50 m journey northeast can be broken down into a north component (50 m × cos(60°)) and an east component (50 m × sin(60°)). For the 30 m jaunt southeast, we have equal components in the south and east directions since southeast translates into a 45° angle from either cardinal direction. Finally, the 35 m southward leg contributes only to the southern component.
The 45° angle likely comes from breaking down the southeast directed segment into its southward and eastward components, as southeast equates to 45° south of east or 45° east of south in the context of standard cardinal directions.