Sandy Wood
Brain Game: L-ementary
by Sandy Wood - October 9, 2009 - 7:30 AM

THE SOLUTION:

blueboxa

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Comments (14)
  1. You could also trace one line from LU corner to RD corner and another between the other two points, resulting in four identical triangles

  2. What if you just drew 3 lines outward from the inside (center of whole pic) corner of the “L”? One out to the top left corner, one to the bottom left corner, and one to the bottom right? It would make two larger and two smaller triangles, but the puzzle just said make the same shape, which they would be. I think…

  3. I have done enough puzzles to see this one fairly quickly, however, my freind divided it into four isoceles right triangles, two small and two large. Since the puzzle specified \identically-shaped\ I would have to say he was technically correct in his solution.

  4. You folks are absolutely right. Even though I intended to mean “same size AND shape,” your answer does indeed work based on the way I phrased the instructions. Nice job!

  5. What about drawing 3 “L”‘s inside the shape, facing the same way as the blue “L”? Again, they all would be the different sizes, but it would work.

  6. I also came to the triagle conclusion. In order to make the triangles the same size, you could take the two larger triangles and split them in two in order to make 6 triangles of identical size.

  7. @Tdl – I don’t think you could manage that and actually keep them the same shape. To be the same shape, the proportions between the sides would have to remain constant.

  8. Four right triangles, TL to BR then BL to inner vertex of the ‘l’

  9. @Tdl … I liked the idea so I worked it out. If the height of the figure is X, than the width of the largest “L” would be 0.1591(X), the next 0.1338(X), the next 0.1125(X) and the last and smallest 0.0946(X). Of course I rounded to the fourth decimal.

  10. I also came up with the triangle solution. Demonstrates the difference between “similar” and “congruent” quite well.

  11. @Richard… If they’re not similar anyway, is there any reason there couldn’t just be, for instance, three skinny ones and a fat one?

  12. @Betsy, Similar polygons are polygons for which all corresponding angles are congruent and all corresponding sides are proportional. Keeping the sides proportional would be a crucial.

  13. I’m glad to see so many others came up with 4 triangles and it wasn’t just me.

  14. I think the instructions could have been a bit vaguer.

    No indication whether or not the whole shape is a square. Also, what kind of description is “identically-shaped parts?” Doesn’t a 2 x 6 rectangle and a 4 x 12 identically shaped rectangles, just not the same measurements…maybe I just don’t get the lingo. Odd wording I guess.

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