Geometric Diagrams (3) and (4): Rectangle Partition and Line Segment Representation #3397058 (License: Personal Use)

Diagram (3) presents a horizontal rectangle partitioned vertically, with the left half filled by dense vertical lines and the right half left blank-commonly used to represent fractions or proportional areas. Diagram (4) shows a thin diagonal line intersected by a thicker black segment near its center, possibly indicating a highlighted portion, measurement marker, or physical object like a rod or pointer.

These diagrams appear in vintage mathematics textbooks, engineering schematics, or pedagogical materials illustrating concepts like area division, ratios, vector segments, or instrument representation. User intent typically involves understanding visual notation in technical or educational contexts.