The starting point of the W-Wing is two bi-value cells (in which only the same two candidates occur), which do not see each other, and these two cells can see a conjugate pair with one of these candidates. The other candidate value in the bi-value cells can be removed from the intersection of the output fields.
In cells F4 and H6 (highlighted in yellow), only the numbers “7” and “5” occur. In column 8, the number “7” is a conjugate pair and appears in the rows related to the yellow cells.
In this configuration, the number opposite to “7”, which is “5”, can be eliminated at the intersection (F4).
One more example:
Always on the lookout for technical variations. In box 6, the solution for the number “2” will be in cell D8 or cells D9 or E9. Either choice will delete the number “8” in cell B8.
Always pay attention to variations in techniques. There’s no W-Wing here. But what happens when you analyze the possible solutions?.
