Practise: X-Wing
Follow one digit only: which two rows or columns keep 2 in the same two cross-lines?
The prepared notes show every 2 that matters. Find the two source lines with the same two cross-lines; do not place a digit yet.
Example 1 of 4
Your turn first
Where can 2 no longer stay?
Look only at the prepared 2-notes. Find two rows or columns with the same two cross-lines, then identify the other 2-notes on those cross-lines to remove. Do not place a digit yet.
Remember
An X-Wing is simple: two source lines offer one digit in the same two cross-lines. Those cross-lines must receive the digit from the rectangle, so every other note for it there disappears. The X-Wing itself does not place a digit.
Put it to use
Where you will meet it
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