Draw an equilateral triangle. Divide it into four identical shapes. Remove the bottom left-hand shape. Now divide the resulting shape into four identical shapes.
(In reply to I can do this! (spoiler)
by Steve Herman)
p.s. -- I just searched unsuccessfully for a name for an isosceles trapezoid with three equal sides. Anybody?
You know, as common as the shape is, I've never seen it given a name. You can call it the triamond: http://mathworld.wolfram.com/Triamond.html
Posted by Jer
on 2013-04-29 12:55:44