The tilings shown use as few tiles as I know how, and are not necessarily unique under this condition. If you find a tiling with fewer tiles, please write.
See also Similar Polyaboloes Tiling a Triangle, Similar Polyaboloes Tiling a Home Plate Hexabolo, and Similar Polyaboloes Tiling an Octagon.
The standard reference for tilings by polyforms at various scales is Dr. Karl Scherer's A Puzzling Journey to the Reptiles and Related Animals (1987).
Last revised 2017-11-25.