XY-Wing
The XY-Wing technique is similar to the “X-Wing,” but it’s based on a triangle instead of a rectangle. Let’s take a look at how we can spot this pattern.
- Let’s start with the following example
- First, locate a cell that contains exactly two candidates. This cell is referred to as the “Base” cell. Next, identify two other cells that align with the Base cell but belong to different units. In these two cells, one of the candidates must match one of the candidates in the Base cell, while the other candidate must be present in both of these aligned cells.
- Regardless of the final value in the base cell, one of the highlighted cells will contain the value 1
- That means that the value 1 can’t be placed in any cell that sees both highlighted cells
