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#1 2010-06-25 14:59:24
- lakeheadca
- Member
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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
#2 2010-06-25 15:11:08
- ZHero
- Real Member
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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.