Difficulty: Extreme!

Ziqi’s teacher loved puzzles, and posed a difficult challenge: “Draw five dots on a piece of paper. Now, connect each dot to every other dot. Each pair of dots needs to be connected by a line, which doesn’t need to be straight.”

Ziqi did this, and the picture looked like a star inside a pentagon:Five blue dots in a circle, connected by purple lines making a star inside a pentagon shape.
The challenge continued: “Now, do the same again, only your lines can’t touch or cross over other lines or dots.”

Ziqi spent ages thinking about this challenge. It seemed impossible, but Ziqi came up with a solution! They cut a strip of paper, put a dab of glue on each end and made a little bridge on their page. Then the puzzle was possible.

Can you use one bridge to solve the puzzle too?

Scroll down or click for a hint, or the answer!

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Brainteaser hint

Try this challenge with a pencil and an eraser to undo mistakes. Draw as many lines as you can without making a crossing and then add in a bridge. Remember that the lines don’t need to be straight!

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Brainteaser answer

To finish this puzzle, you need to draw 10 lines.

  1. Pentagon shape formed with lines connecting dots with an inner triangle.The first 7 lines are quite easy:
  2. Shape as previous with lines looping dot one to three and dot three to dot five.The next 2 are a bit trickier:
  3. Image as previous with a bridge connecting dot two to dot five.And the last line needs a bridge:

There are many other solutions to this puzzle, but they all need a bridge somewhere!

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2 responses

  1. Vayda Avatar

    I loved this challenge! We did something very similar in a STEM challenge we did at school! It was so fun and I found it challenging and very beneficial!

  2. Vayda Avatar

    You had to connect 4 dots with only 5 lines. It was very challenging and I would definitely recommend it as it enhances both the creative and logical side of your brain!

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