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## 'Flip' printed from http://nrich.maths.org/

I'd like you to imagine a large square piece of rigid plastic,
maybe perspex or pretend glass.

On it is marked a square made up of 6 x 6, that is 36, dots:

Someone marks a capital or big "F" in this way:

You are pretending to hold this in
front of you.

You are going to flip it over in
front of you along imaginary lines which I've drawn in blue on the
diagrams below. You could do this by imagining you are
holding each end of the blue line with a hand and turning the sheet
over.

Each time start with the "F" as shown above, and in your mind find
how it will look when you flip it along the blue line.

First this one:

Try to describe to someone how it will
now look to you.

Now try this one:

If you feel you could go further try
this one:

And my last suggestion as a different
way of flipping is:

How did you get on?

Talk to others about the
experience.

If that's been ok. then use this next shape instead of the "F"
and do the same flips.

Can you tell where the triangle will be?