OK So you have 34 x 5... You would do 4 x 5 and that would be 20.. so you put the 0 on the bottom (below the line) and you put the 2 above the 3. You then do 3 x 5 and that would be 15 but you can't forget about the 2 so you would add 2 to 15 and that would be 17... so you put 17 beside 0.
So 34x5=170