Colour Subtraction with Overlapping Circles

This example demonstrates subtractive colour mixing by overlapping red, green, and blue circles, visualising the principle of colour subtraction. Core mathematical concepts include circle geometry, set intersection and union, and the subtractive colour model. Construction uses the Circle command to create multiple circles (objects A–F) positioned by numerous point objects (a, b, c, …, J) and defines colour variables rr, gg, bb together with text labels tekst1‑tekst6 for numeric read‑outs. Suitable for middle‑ and high‑school geometry lessons, introductory optics/colour science, and as a GeoGebra advanced construction showcase.