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#1 2006-02-28 15:30:27
- naturewild
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- Registered: 2005-12-04
- Posts: 30
Similar triangles
This question is really easy but I'm weak in similar triangle.. I dont know how to do it.
In triangle ABC, D and E are in AB and AC respectively such that DE is parallel to BC, AD = 3, DB = 4, and triangle ADE = 81. Determine
1. triangle ABC
2. quadrilateral DBCE
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#2 2006-02-28 15:49:03
- mikau
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- Registered: 2005-08-22
- Posts: 1,504
Re: Similar triangles
triangle ADE = 81 makes no sense. Do you mean ADE = 81 degrees or something?
A logarithm is just a misspelled algorithm.
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#3 2006-02-28 15:55:46
- naturewild
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- Registered: 2005-12-04
- Posts: 30
Re: Similar triangles
oh those are the areas I mean.
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#4 2006-02-28 18:03:57
- krassi_holmz
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- Registered: 2005-12-02
- Posts: 1,905
Re: Similar triangles
S[ade]:S[abc]=3:7
S[dbce]=S[abc]-S[ade]
So you can do it all alone.
IPBLE: Increasing Performance By Lowering Expectations.
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#5 2006-02-28 18:14:48
- naturewild
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- Registered: 2005-12-04
- Posts: 30
Re: Similar triangles
I tried doing it that way. Let's say x = triangle ABC
ADE / ABC = 3 / 7
81/x = 3/7
x = 189
But the answer is 441
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#6 2006-03-01 06:57:42
- John E. Franklin
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- Registered: 2005-08-29
- Posts: 3,588
Re: Similar triangles
Did you say that D is along AB and E is along BC?
If so, then DE is parallel to AC, not BC.
igloo myrtilles fourmis
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#7 2006-03-02 20:45:01
- boyhuesd
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- Registered: 2006-03-02
- Posts: 1
Re: Similar triangles
o!
It very easy!
ec! ec!
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