This is a lesser known version of "
nine dots."
There are 12 dots arranged in a 3 by 4 square similarly to "nine dots." Connect all of them with 5 straight lines without lifting your pencil, ending at the same point you started at. You cannot cross the same point twice, but the lines themselves may cross. There are no tricks here!
Bonus: Try doing the same with a 4 by 4 square with 16 dots and 6 lines (it's similar).
(In reply to
re: solution to 3x4 by Vee-Liem Veefessional)
first he labeled his rows.
If you draw a graph and label the horizontal i and the verticle j, you will see that the horizontal row will be the one with 4 dots in it that david labeled from 0 to 3. and of course the verticle row has 3 dots labeled 0 to 2. So the bottom left dot is in the position of 0,0. Now plot david's points and you will see they connect perfectly.
re(2): solution to 3x4
