Respuesta :
Answer;
-Reference point
The x represents the reference point on a motion map.
Explanation;
-Motion maps are another way to represent the motion of an object. (other representations are graphical and mathematical models).
-Motion maps are a visual way to represent an object’s motion at various time
-. A reference point is a place or object used for comparison to determine if something is in motion. An object is in motion if it changes position relative to a reference point.
-The relationships between motion and reference point is that When an object changes position over time relative to a reference point, the object is in motion. This means that there relationship is they are similar.