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#1 2010-06-25 14:59:24

lakeheadca
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Geometry: grade 11 problem#1

Give triangle ABC and EDC, c is the midpoint of
__        __
BD and AE.

prove: AB|| DE


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#2 2010-06-25 15:11:08

ZHero
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Re: Geometry: grade 11 problem#1

∠ ACB = ∠ DCE (vertically oppsite ∠s)

AC/DC = BC/EC = 1/2 (given)

∴ ACB∼DCE (SAS similarity)

∴ ∠ABC = ∠DCE

AB||DE (alternate angles are equal)


If two or more thoughts intersect with each other, then there has to be a point.
 

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