Geometric Demo of the Segment Addition Postulate

This example constructs points on a straight line and visually demonstrates the Segment Addition Postulate: when a point lies between two others, the whole segment length equals the sum of the two smaller segment lengths. The key mathematical ideas include linear/collinear points, segment length relationships, and the decomposition of a segment into subsegments to form an equality. In GeoGebra, it is built using the commands “Segment” and “Point”, together with “LaTeX” text labels to present key notation and the length relationship. The construction uses objects such as points A, B, C, segments AB, BC, and the combined segment AC, along with multiple text objects (text1–text6) to label the diagram and emphasize the postulate. Suitable for middle school geometry lessons and introductory geometry practice, as well as for reinforcing foundations before applying similar reasoning in inequality, trigonometry, or interval-based methods.