The concepts of line of action of a force are fundamental to the study static and dynamic mechanical systems. However, this concept is a little explored in textbooks of both graduate school as a high school, at most, only mentioned. This paper presents a recall to concepts about lines of action for force pairs and proposes an alternative geometric method for determining the point of resultant force action, emphasizing its direction and sense. This method was called "parallel components method".
line of action; simple machines; vectorial graphic method
