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# Isometries with ducks Tweet

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1. Isometries with ducks
Hi, please look at attached pic.

How is that true what it says, the rows have different alignments, how is the move up not vertical? Seems counter intuitive to me

Read it a few times and stared at it and cannot understand how this is true.

Surely the top duck after the translation would be directly above the bottom duck, like a mirror image?

Is this something to do with a parallelogram or something?
Attached Thumbnails

Last edited by SubAtomic; 16-07-2012 at 18:54.
2. Re: Isometries with ducks
It's and not . The latter would be vertical, but the former is diagonal. Remember that you moved it 4 units to the left first, not 3. Is this what you were asking?
3. Re: Isometries with ducks
I fail to see the problem.

Deperately trying to think of a duck joke.
4. Re: Isometries with ducks
(Original post by nuodai)
It's and not . The latter would be vertical, but the former is diagonal. Remember that you moved it 4 units to the left first, not 3. Is this what you were asking?
I mean if it goes one unit back to the right and one unit up, how is the triangle not a right triangle?

Cannot fathom how a move 4 units left followed by a move 1 unit right and 1 unit up is not directly above one of the bottom ducks, the alignments are skew, confused.

Think I may be making a false assumption possibly.

I am Was counting each duck as a unit which is where I went wrong.

So the middle of the black duck on the bottom line would be at (-2,0) for arguments sake?
Last edited by SubAtomic; 16-07-2012 at 16:37.
5. Re: Isometries with ducks
(Original post by SubAtomic)
I mean if it goes one unit back to the right and one unit up, how is the triangle not a right triangle?

Cannot fathom how a move 4 units left followed by a move 1 unit right and 1 unit up is not directly above one of the bottom ducks, the alignments are skew, confused.

Think I may be making a false assumption possibly.
I don't think the vertical 'units' are the same size as the horizontal ones here. A vertical unit takes you up to the next line of ducks, whereas a horizontal unit moves you half the length of a duck. So you move 3 half-duck-lengths left and jump one row up... which is why it's not in line with a duck on the row beneath. Does this answer your question, sort of?
6. Re: Isometries with ducks
(Original post by nuodai)
I don't think the vertical 'units' are the same size as the horizontal ones here. A vertical unit takes you up to the next line of ducks, whereas a horizontal unit moves you half the length of a duck. So you move 3 half-duck-lengths left and jump one row up... which is why it's not in line with a duck on the row beneath. Does this answer your question, sort of?
Yep, saw my error, assumptions and all

You can all duck out this thread now, thanks
7. Re: Isometries with ducks
(Original post by ghostwalker)
Deperately trying to think of a duck joke.
Hard to come by