Basic Sudoku techniques #4

Another strategy in solving Sudoku is to find the missing digit by checking across row, downward column AND within a box. This is according to the rules of Sudoku that every row, column and box must contain unique digits from 1 to 9 (non-recurring).

Example:
Digit 9 is the answer to Cell D2. By checking
-Existing digits across Row 2 are 2, 3 and 4.
-Existing digits at Column D are 1, 8 and 6.
-Existing digits in Box 2 are 1, 7, 8 and 5.

While checking digits on row and column, quite often we tend to forget the digits in box, something important for us to take note while solving Sudoku.

It could have situation that there are two possible missing digits, try jotting down the digits on the top right corner of the cell.