IIn a blue square A1A2A3A4 
	  with side length 'a', the trisectors of angles A1, A2, A3, A4 and 
	  diagonals intersect at points B1, B2, B3, B4, C1, C2, C3, C4, D1, D2, D3, ..., D12 
	  as shown in the figure. 
	  We need to prove the following statements: (1) B1B2B3B4 is a 
	  square (yellow); 
	  (2) D1D4D7D10 is a square 
	  (red); (3) C1C2C3C4 is a square 
	  (orange) ; (4) D1D2...D12 is a regular dodecagon 
	  (green); (5) Area 
	  of B1B2B3B4 = 
	   ; (6) 
	  Area of B1B2B3B4 = 2 times the 
	  area of D1D4D7D10; 
	  (7) Area B1B2B3B4 = 3 times 
	  the area of C1C2C3C4; 
	  (8) Area 
	  D1D2...D12 = 3/4 times the area of B1B2B3B4.
; (6) 
	  Area of B1B2B3B4 = 2 times the 
	  area of D1D4D7D10; 
	  (7) Area B1B2B3B4 = 3 times 
	  the area of C1C2C3C4; 
	  (8) Area 
	  D1D2...D12 = 3/4 times the area of B1B2B3B4.
 

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	Problem 1357: Regular Dodecagon, Concurrency, Collinearity
	Problem 1358: Square, Regular Dodecagon
	  Kurschak's Dodecagon
Ten problems: 1321-1330
						
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