Here's how 2-D logic works (it's an easy one on this puzzle): Look at the 7 on the bottom row. If you place it on the left-hand side, then fill in the vertical squares off it, does it work with the row above the 7? No, because the 3rd column has a 1, meaning the row above the 7 can't have the 4 on the left. So there are some squares that can be "x"d out. Keep going until you get stuck. Then try it on the right-had side. You'll find (in this puzzle) that there is only one place where the 7 can go.
I hope that helps... it seems that this is where you're having a lot of trouble with the puzzles. :)
Here's how 2-D logic works (it's an easy one on this puzzle):
Look at the 7 on the bottom row. If you place it on the left-hand side, then fill in the vertical squares off it, does it work with the row above the 7? No, because the 3rd column has a 1, meaning the row above the 7 can't have the 4 on the left. So there are some squares that can be "x"d out. Keep going until you get stuck. Then try it on the right-had side.
You'll find (in this puzzle) that there is only one place where the 7 can go.
I hope that helps... it seems that this is where you're having a lot of trouble with the puzzles. :)
I do this in puzzles but didn't know it had a term!