This technique is similar to "Pointing Pairs," but it's used when a note has a number repeated in three cells in the same block, in the same row or column. This means that the given number is in one of the three cells of the column or row, so we can exclude it from the other cells in the adjacent blocks.
To get a better handle on the "pointing triples" technique, let's take a look at an example. We used notes to flag which numbers would be in the block and row. In the target block, the nine shows up three times in the row, and it also shows up once in the row outside the block.
The Sudoku rules say that the nine has to show up at least once in the left block. So you can just remove the nine from the other cells in the row. The decision is now more straightforward.
The "Pointing triples" technique works for rows and columns.
The technique is pretty straightforward, but it lets you narrow down the number of choices in your notes. That means you're getting closer to solving the Sudoku. As with the other methods we've talked about, you can combine "pointing triples" with other techniques. This method is great for any level of Sudoku, from the easiest to the most difficult.