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Simple Geometry

  1. Sep 25, 2004 #1
    Oddly enough, i forget my geometry laws two days before the test.

    If ABCD is a parallelogram where x and y are on the midpoints of AD and BC. Prove that BX and DY are parallel. I understand one would have to prove that corresponding angles are equal. thus, AHX would equal CMY, and ADM would equal BHC.

    My question is: if a large triangle and a smaller triangle have proportional sides (e.g. 1/2), would the angles be proven equal?
  2. jcsd
  3. Sep 25, 2004 #2


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    Hey, you're not supposed to forget until AFTER the test!

    Yes, if two triangles have sides in proportion, then they are "similar" triangles and have the same angles.
  4. Sep 25, 2004 #3
    Thank you HallsofIvy for reminding me about the similar triangles, as well as to forget everything i know after the test. :)
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