Ellipse Construction via Focus Definition

This GeoGebra example demonstrates constructing an ellipse using the locus definition, where the sum of distances from any point on the curve to two fixed foci remains constant. Core mathematical concepts include ellipse geometry, foci, constant sum of distances, locus, and analytic geometry. Construction utilizes GeoGebra objects labeled a (semi-major axis parameter), A and B (foci), and d (directrix or distance parameter), employing tools such as Locus, Circle, and Segment to dynamically visualize the ellipse's geometric properties. Ideal for high school analytic geometry, pre-calculus, or classroom demonstrations, it helps students intuitively grasp the focus-directrix and focus-sum definitions of an ellipse.