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		| Earl 
 
 
 Joined: 30 May 2007
 Posts: 677
 Location: Victoria, KS
 
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				|  Posted: Sat Jun 20, 2009 2:07 am    Post subject: June 20 VH |   |  
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				| There are multiple and complex routes, but also a single bullet. 
 
 A Solution:  xyz-wing (124) elminates the 4 in R5C6 and solves the puzzle.
 
 Early Earl
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		| crunched 
 
 
 Joined: 05 Feb 2008
 Posts: 168
 
 
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				|  Posted: Sat Jun 20, 2009 4:24 am    Post subject: |   |  
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				| This is after all the basics, according to me. It is enough for earl's xyz solution.
 Earl's xyz is what I used for a solution.
 
 
 
  	  | Code: |  	  | +-------------+-------------+--------------+
 | 8   2    9  | 147 146 5   | 467 1346 136 |
 | 147 14   6  | 8   9   3   | 47  5    2   |
 | 147 3    5  | 147 146 2   | 9   1468 168 |
 +-------------+-------------+--------------+
 | 2   169  7  | 3   5   16  | 68  689  4   |
 | 3   1469 14 | 124 8   146 | 5   269  7   |
 | 5   46   8  | 24  7   9   | 1   236  36  |
 +-------------+-------------+--------------+
 | 14  5    2  | 6   3   148 | 48  7    9   |
 | 9   8    3  | 5   14  7   | 2   146  16  |
 | 6   7    14 | 9   2   148 | 3   148  5   |
 +-------------+-------------+--------------+
 
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 Play this puzzle online at the Daily Sudoku site
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		| tlanglet 
 
 
 Joined: 17 Oct 2007
 Posts: 2468
 Location: Northern California Foothills
 
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				|  Posted: Sat Jun 20, 2009 2:32 pm    Post subject: |   |  
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				| A second xyz-wing exists involving some of the same cells. xyz-wing 146 deletes the 1 in r5c4.
 
 Ted
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		| Louise56 
 
 
 Joined: 21 Sep 2005
 Posts: 94
 Location: El Cajon, California  USA
 
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				|  Posted: Sat Jun 20, 2009 2:40 pm    Post subject: |   |  
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				| Could someone explain to me how the xyz wing works?  When I did the puzzle I could see that I couldn't have a 4 in r7c1, but that is just trial and error.  Thanks. |  | 
	
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		| Marty R. 
 
 
 Joined: 12 Feb 2006
 Posts: 5770
 Location: Rochester, NY, USA
 
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				|  Posted: Sat Jun 20, 2009 3:48 pm    Post subject: |   |  
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				|  	  | Louise56 wrote: |  	  | Could someone explain to me how the xyz wing works?  When I did the puzzle I could see that I couldn't have a 4 in r7c1, but that is just trial and error.  Thanks. | 
 I'll try. The basic rule is to start with a trivalue cell we'll call XYZ. Then there must be in the same box a cell we'll call XZ. Then the XYZ cell must see a cell in another box we'll call YZ. Any cell that sees all three of XYZ, XZ and YZ cannot contain Z. In this case, the three cells are the 124, 24 and 14 in boxes 4 and 5. R5c6 sees all three and cannot contain a 4.
 
 For more information, just Google XYZ-Wing and you'll find explanations clearer than mine. This technique is an important one for any player to have in his/her arsenal.
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		| hughwill69 
 
 
 Joined: 20 Jun 2009
 Posts: 1
 Location: Birmingham England
 
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				|  Posted: Sat Jun 20, 2009 7:55 pm    Post subject: Louise56 wrote: |   |  
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				| Could someone explain to me how the xyz wing works? When I did the puzzle I could see that I couldn't have a 4 in r7c1, but that is just trial and error. Thanks. 
 Marty R. replied:
 
 For more information, just Google XYZ-Wing and you'll find explanations clearer than mine.
 
 
 Try this- I found it one of the clearest:
 http://www.brainbashers.com/sudokuxyzwing.asp
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		| Louise56 
 
 
 Joined: 21 Sep 2005
 Posts: 94
 Location: El Cajon, California  USA
 
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				|  Posted: Sat Jun 20, 2009 8:14 pm    Post subject: |   |  
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				| Thank-you for your explanation and the reference.  |  | 
	
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		| Marty R. 
 
 
 Joined: 12 Feb 2006
 Posts: 5770
 Location: Rochester, NY, USA
 
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				|  Posted: Sat Jun 20, 2009 9:14 pm    Post subject: |   |  
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				| Hi Hughwill69, welcome to the forum. Brain Bashers does indeed offer a good explanation. |  | 
	
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