System of Inequalities: Visualizing Feasible Regions and Geometric Constraints

① This example demonstrates how multiple inequalities jointly constrain a planar region, forming a feasible area bounded by curves, and visually reveals the solution set of a system of inequalities. ② Core mathematical concepts include systems of linear or nonlinear inequalities, intersection of regions, boundary determination, and geometric relationships involving angles and shapes; it also touches on point sets in the complex plane and the role of step functions in partitioning regions. ③ Construction highlights: based on the summary, objects a, b, c, and d are used as parameters or constraints, likely employing GeoGebra's inequality commands or region-filling tools, combined with dilation and angle tools to adjust the view and clearly display the feasible region's boundaries. ④ Suitable for high school or early college students learning systems of inequalities, introductory linear programming, or coordinate geometry, and for teachers demonstrating dynamic changes of solution sets in class.