A linear relationship between two attributes is a relationship wherein one attribute changes at a constant rate relative to the other attribute. A linear mapping between two entities is a mapping that keeps the relationships between the attributes of the entities linear. Evidently, understanding linear relationships can help us understand: (1) how to solve for linear equations and systems of linear equations, (2) geometric objects and operations such as lines, planes, translation, rotation, etc., and (3) vectors (which is related to geometry but can be extended beyond; see: Vectors).
Basics…