Before I reveal how to create a Venn diagram plotter using basic trigonometry and Excel, I would like to thank my co-work Shea for challenging me to solve this problem. What is the problem? Given the areas of two circles and how much they overlap, plot a Venn diagram showing their relation in space. What must you know first? In order to understand my solution, you need to have some math background in trigonometry, as well as some macro-writing experience in Excel. How to solve it? We can easily draw circles in Excel, re-size them, and define their coordinates. Finding out the diameters of the circles given their areas is easy: A=πr². The y-coordinates of the two circles are essentially the same. The x-coordinates of the two circles can be determined if the distance between their loci is known. I define d to be this distance, h to be the length of their common chord, and everything else as shown in the diagram below. Imagine the two circles are just starting to touch e
