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#1 2006-03-01 14:30:27

naturewild
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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

#2 2006-03-01 14:49:03

mikau
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Re: Similar triangles

triangle ADE = 81 makes no sense. Do you mean ADE = 81 degrees or something?


A logarithm is just a misspelled algorithm.

#3 2006-03-01 14:55:46

naturewild
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Re: Similar triangles

oh those are the areas I mean.

#4 2006-03-01 17:03:57

krassi_holmz
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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.

#5 2006-03-01 17:14:48

naturewild
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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

#6 2006-03-02 05:57:42

John E. Franklin
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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

#7 2006-03-03 19:45:01

boyhuesd
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Re: Similar triangles

o!
It very easy!
ec! ec!

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