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# Seeing Rhombuses

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Age 7 to 11

Challenge Level

- Problem
- Getting Started
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Thank you to everybody who sent in their ideas about this game. Most people found that the easiest way to win was by making a square, which is a special type of rhombus, so the solutions are very similar to the solutions for Seeing Squares.

Dhruv at The Glasgow Academy in the UK sent in this image:

Dhruv said:

I decide where to place my dot depending on what the opponent plays. You can beat the computer if it goes first but it is difficult.

Thank you for sharing these ideas with us, Dhruv. I can see lots of ways that you can win from the position in the picture!

William described a similar strategy, and explained where the computer would make its moves:

Place 3 dots in a row on the second line (just below the first line)

The computer will make its move under/on top of the middle shape

Then you have to place your move on the opposite the computer made (up or down the middle dot)

The computer will try to prevent your move by going left or right

You make your move the opposite where the computer made, and you now have a victory.

This is a good strategy - we were also sent similar explanations by Hogan at Banstead Prep School and Sebastian at The British School Al Khubairat in UAE.

We received a few solutions from the children at The British School Al Khubairat. Charlie explained a strategy which relied on making triangles:

I tried many approaches, however, in my most useful method, I tried to create triangles (which I would later make into a rhombus). Making many triangles allows ways you can change your shape to allow the shape of a rhombus.

Can you see the triangles that Charlie has made in this solution? I wonder if there is a way to adapt this strategy to make non-square rhombuses?

Shafin had a similar idea that also involved making triangles:

If you do 1, then 2, then 3, then you will force the computer to go to 6. Then, you should go to 4 so you trap the computer. Finally, go to the remaining dot to win!

Thank you all for sharing these ideas with us.