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84 = 85?

  1. May 3, 2010 #1
  2. jcsd
  3. May 3, 2010 #2


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    Re: 84=85?

    Bit different version of a old rube.

    For the created shape to be a rectangle you need to have the slopes of the red and green triangles (3/8) be equal to the slope of the angle of the other 2 shapes (2/5).

    Since .4 <> .375 that is not a rectangle and you cannot get the area by multiplying sides.
  4. May 4, 2010 #3


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    Re: 84=85?

    But still amusing!
  5. May 10, 2010 #4
    Re: 84=85?

    So is it safe to say that in the 5x13 "rectangle", there is a triangle of area ONE unit with a vertex in the top right corner and two vertices near the bottom left corner?

    No, that can't be right, since the slope changes from 3/8 to 2/5...
    So vertices:
    1) top right corner (13, 5)
    2) at "point" (5,2)
    3) bottom left corner (0,0)
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