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		| Earl 
 
 
 Joined: 30 May 2007
 Posts: 677
 Location: Victoria, KS
 
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				|  Posted: Sun Mar 15, 2009 3:38 am    Post subject: March 15 VH |   |  
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				| One shot. (389) xy-wing. 
 Early Earl
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		| swando 
 
 
 Joined: 09 Mar 2009
 Posts: 22
 Location: Surrey, BC. Canada
 
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				|  Posted: Sun Mar 15, 2009 9:48 am    Post subject: |   |  
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				| 389 it was! |  | 
	
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		| cgordon 
 
 
 Joined: 04 May 2007
 Posts: 769
 Location: ontario, canada
 
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				|  Posted: Sun Mar 15, 2009 1:31 pm    Post subject: |   |  
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				| I don't like looking for xy wings - too painful. So for me it was an x-wing on <3>:  two Type 4 URs (15) and (49) and another x-wing on <9>. |  | 
	
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		| Clement 
 
 
 Joined: 24 Apr 2006
 Posts: 1113
 Location: Dar es Salaam Tanzania
 
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				|  Posted: Sun Mar 15, 2009 1:33 pm    Post subject: |   |  
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				| I used two XY-Wings:- 1) XY-Wing {359} with Pivot {5,3}r5c5 eliminating 9 in r8c2
 2) XY-Wing {389} with Pivot {3,8}r5c3 eliminating 9 in r7c2 solves the puzzle. However, the 389 XY-wing was enough.
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		| Louise56 
 
 
 Joined: 21 Sep 2005
 Posts: 94
 Location: El Cajon, California  USA
 
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				|  Posted: Tue Mar 24, 2009 2:46 pm    Post subject: 15 March VH XY wing |   |  
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				| Could someone explain to me the 389 XY wing in this puzzle?  I understand the XY wing when it is a rectangle, but this one appears not to be.  I couldn't solve the puzzle. Thanks! |  | 
	
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		| wapati 
 
 
 Joined: 10 Jun 2008
 Posts: 472
 Location: Brampton, Ontario, Canada.
 
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				|  Posted: Tue Mar 24, 2009 3:06 pm    Post subject: Re: 15 March VH XY wing |   |  
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				|  	  | Louise56 wrote: |  	  | Could someone explain to me the 389 XY wing in this puzzle?  I understand the XY wing when it is a rectangle, but this one appears not to be.  I couldn't solve the puzzle. Thanks! | 
 
 The cell marked with "@" can only be a 3 or an 8.
 That means that one of the cells marked with a "#" must be a 9.
 All the cells marked with a "/" cannot be a 9 because they "see" both 9s.
   
 
  	  | Code: |  	  | .---------------------.---------------------.---------------------. | 489    5      389   | 3489   2      3489  | 1      6      7     |
 | 4789   389    1     | 34789  39     6     | 34     2      5     |
 | 47     6      2     | 3457   1      3457  | 34     8      9     |
 :---------------------+---------------------+---------------------:
 | 5      2      /4    | 89     7      89    | 6      3      1     |
 | 19    #39     /6    | 135    35     2     | 8      7      4     |
 | 18     7     @38    | 6      4      13    | 5      9      2     |
 :---------------------+---------------------+---------------------:
 | 3      /49    7     | 1459   8      1459  | 2      15     6     |
 | 6      /489  #89    | 2      59     1459  | 7      15     3     |
 | 2      /1     5     | 37     6      37    | 9      4      8     |
 '---------------------'---------------------'---------------------'
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		| Louise56 
 
 
 Joined: 21 Sep 2005
 Posts: 94
 Location: El Cajon, California  USA
 
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				|  Posted: Tue Mar 24, 2009 5:15 pm    Post subject: |   |  
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				| Thank-you Wapati for a great explanation.  I have always had a mental block with y wings.  It's hard to locate them, but your logic is clear and simple. |  | 
	
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		| wapati 
 
 
 Joined: 10 Jun 2008
 Posts: 472
 Location: Brampton, Ontario, Canada.
 
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				|  Posted: Tue Mar 24, 2009 5:16 pm    Post subject: |   |  
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