Then you do the same for 2 through 9. After you finish 9,
now you have to go back
and repeat it for 1 through 9 again because numbers that have been
filled in will then
allow you to put more numbers in more squares that you could not do the
After you found all those, look for spaces that can be filled in
along rows and columns.
Also look for squares in boxes that can be filled since every box
has to have 1 through 9.
See future lessons on how to look for those that can be detected.
NEXT LESSON 2