I am pretty new to Sudoko, but I am working the puzzles in the back of the book. I am stumped on this one:
2..|...|581
...|51.|.92
.15|2..|..6
---+---+---
359|..2|817
628|173|954
147|895|623
---+---+---
.72|356|14.
5.1|..4|.6.
.6.|..1|..5
There seems to be no way to place a number without guessing. (Of course I have the solution, and the numbers already there match the solution.)
Could someone tell me a rule that applies?
Thanks,
John