Terri, this is my first time giving advice, so I hope my explanation isn't too muddled.

{

Edited to remove a missed possibility}

One thing that can be done is in the center row (row 5):

{3,9} {1} {5} {2,6,8} {2,4,6} {2,4,6,8} {7} {3,4,6,9} {4,6}

Row 5 has a hidden pair of 3 9 that can only be found in cell 1 and 8, so you can eliminate the 4 & 6 from the choices in cell 8.

There's lots of neat things going on in this puzzle.

Try the middle 3x3 box on the bottom (box #8):

It eliminates down to looking like this

- Code: Select all
`{4} {7} {1}`

{2,6,9} {5} {2,6,9}

{2,3,6} {1} {2,3,6}

The only two places that the 3 can reside in this box is in the bottom row (row 9)...

...which looks like this:

{2,3,7} {9} {1,2,3,6,7} {2,3,6} {8} {2,3,6} {1,2,4} {5} {1,4,7,6}

But you know the 3 for row 9 is in either column 4 or 6, so you can eliminate it from c1 & c3.

{2,7} {9} {1,2,6,7} {2,3,6} {8} {2,3,6} {1,2,4} {5} {1,4,7,6}

Looking back at box #8, you can do the same thing for the 9, which

must be in row 8. You can remove all possibilities of the 9 from row8 c7-8.

Doing this hopefully gets you going!

{Note}Annette's post below is right. My initial post about Box#6 omitted a possibility of another 6, so I had to edit it. The other stuff rings true.

I'm very sorry.