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'...on the Wall' printed from http://nrich.maths.org/
This problem follows on from
Mirror, Mirror...
You might find it helpful to copy this diagram onto
squared
paper .
Reflect the flag in one of the lines. Reflect the resulting image
in the other line.
Can you describe the single transformation you would need to get
from the first flag to the last flag?
Does it matter in which line you reflect first?
Try this with the flag in other positions.
Now try it with lines that meet at $45^{\circ}$ and at $60^{\circ}$
(you might find it helpful to use
isometric
paper
for the $60^{\circ}$ case).
Again, try it with the flag in different positions
Can you predict what single transformation you would need to get
from the first flag to the last flag if the lines meet at
$\theta^{\circ}$?
Can you prove your answer?
If you have enjoyed this problem, you may like to have a go at
Who is the fairest of them all? .