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Homework Help: Geometry proof

  1. Jan 26, 2006 #1
    how do you prove that the line segment joing the midpoint of two sides of a triangle is parallel to and 1/2 the length of the 3rd side?
     
  2. jcsd
  3. Jan 26, 2006 #2

    HallsofIvy

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    Try using "similar triangles".
     
  4. Jan 29, 2006 #3
    I think Basic proportionality theorem is proved before midpoint theorem. Basic proportionality theorem states that if in TrABC, BC||DE, then D and E divides AC and AB in the ratio, same as that of BC:DE.
     
  5. Jan 29, 2006 #4
    The midpoint theorem is a direct conxequence of Baisproportionality theorem.
     
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