Flip
Can you picture where this letter "F" will be on the grid if you
flip it in these different ways?
Problem
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:
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Someone marks a capital or big "F" in this way:
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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:
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Try to describe to someone how it will now look to you.
Now try this one:
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If you feel you could go further try this one:
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And my last suggestion as a different way of flipping is:
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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?
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Move around the blue dots to see what happens when you flip using different lines.
Here you can move the line and try different triangles.
Getting Started
You could focus on one part of the F, or just one
point. Where that will be on the grid once you have
flipped the F? Can you build up a picture of the F
after the flip in this way?
You might like to have some dotty paper to hand to draw the F after you've talked to someone else about it.
You could draw the grid and the F on an overhead transparency, then flip it to check what you have pictured in your head.
You might like to have some dotty paper to hand to draw the F after you've talked to someone else about it.
You could draw the grid and the F on an overhead transparency, then flip it to check what you have pictured in your head.
Student Solutions
Cong from St Peter's Roman Catholic Primary School worked hard at this problem. He sent us these pictures to show the flips:
Horizontal flip:Image

Vertical flip:
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First diagonal flip:
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I'm not sure this first diagonal flipped one is quite right - have another go.
Second diagonal flip:Image

And for the triangle, here is the horizontal flip:
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The vertical flip:
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First diagonal flip:
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And finally, the second digaonal flip:
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Very well done, Cong!