Wesley Lin - Area of Irregular Shapes

Area of Irregular Shapes (The Shaded Area Problem)

I like to call this the "shadow warrior" problems, since a shadow of irregular shape is usually highlighted. This type of question can be really fun, since it requires some creative decomposition of the irregular shape into the "sum" or "difference" or a fraction of regular shapes. How you decompose your shadow might mean the difference between a very fast and simple solution and a convoluted one.