## xyz wing question

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### xyz wing question

I got this puzzle to the following state:
Code: Select all
`*-----------------------------------------------------------* | 5     3     28    | 249   2789  289   | 1     47    6     | | 47    6     9     | 1     3     5     | 478   2     48    | | 247   14    128   | 24    278   6     | 3     5     9     | |-------------------+-------------------+-------------------| | 24    49    5     | 3     249   7     | 4689  168   18    | | 8     149   12    | 6     5     249   | 49    3     7     | | 3     7     6     | 8     49    1     | 5     49    2     | |-------------------+-------------------+-------------------| | 1     2     3     | 7     489   489   | 4689  4689  5     | | 9     8     7     | 5     6     34    | 2     14    134   | | 6     5     4     | 29    1     2389  | 789   789   38    | *-----------------------------------------------------------*`

I thought I had an XYZ wing formed by r4c1, r4c5,r6c5 thereby being able to eliminate the 4 at r4c2. This is not correct since r4c2 is a 4. Can someone please explain why this is not an xyz wing pattern? Thanks for any help with this one.
asajar

Posts: 10
Joined: 09 May 2008

You can only eliminate 4 in cells that see all three cells; i.e., [r4c4] and [r4c6]. However, 4 has already been eliminated from these cells. On the other hand, what about cells [r3c1]/[r2c1]+[r3c4]?
daj95376
2014 Supporter

Posts: 2624
Joined: 15 May 2006

Or get naked in r4....

Luke
2015 Supporter

Posts: 435
Joined: 06 August 2006
Location: Southern Northern California

Thank you for your help--I now fully understand the concept.
asajar

Posts: 10
Joined: 09 May 2008

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