Line Puzzles

Join the Dots 



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K12 Math Puzzles


Join the Dots



Can you connect 9 dots laid out 3x3 using 4 straight lines, without lifting your pencil from the paper?

   Suggested Materials:

4 sticks of uncooked spaghetti and 9 pennies

or 4 toothpicks and 9 Cheerios or other flat breakfast cereal
or whatever other manipulative is handy to simulate the lines and dots


  1. Place 9 "dots" on your desk or table.

  2. Using the 4 sticks experiment with connecting the dots using 4 straight lines. (Or just use pencil and paper.)

   Questions to ask yourself as you work:

  1. Can you do the puzzle if the lines do not cross each other?

  2. Must your lines stay within the grid of dots?

  3. What if you extend a line past the edges of the arrangement of dots?

A hint...


(Don't look 'til you're ready to give up!)

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