Row and Column Cross
Another way to discover numbers is to make a cross by row and column. This consists of focusing attention on a cell and checking what numbers can go in that position, eliminating those that are in the same row or column.
When to use it
Use to place a specific digit inside a box by crossing the rows and columns that already contain it.
Worked example
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Take one digit and find the rows and columns where it already appears.
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Those lines cross into the target box; with a single cell left uncrossed, place the digit there.
Common mistakes
- Crossing only rows or only columns instead of both.
- Stopping after one digit — repeat the cross for every digit the box still needs.
Frequently asked questions
Is cross-hatching the same as scanning?
It is scanning made systematic: you take one digit at a time and eliminate cells box by box until a single square remains.