Question about similar triangles

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Question about similar triangles

Postby maroonblazer on Fri Mar 28, 2014 7:01 pm

My text states the following:






I'm not following how they're getting from:



I fear it's something painfully obvious.

Thanks in advance!
mb
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Re: Question about similar triangles

Postby buddy on Fri Mar 28, 2014 7:10 pm

maroonblazer wrote:

I'm not following how they're getting from:


Me either. I mean, yeh, it's true because that's what areas do. If the shapes are similar then the sides are in proportion in terms of their lengths and the areas are in proportion in terms of the squares of the lengths. So really they should just do A1/A2=b^2/e^2. dunno why they did the rest. Yeh, it's confusing.
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Re: Question about similar triangles

Postby maroonblazer on Sat Mar 29, 2014 2:13 pm

I posted this over on StackExchange and got the following answer:

For two similar triangles, the ratio of the height of the first triangle to the height of the second triangle is equal to the ratio of the base of the first triangle to the base of the second triangle.


http://math.stackexchange.com/questions ... a-question
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Re: Question about similar triangles

Postby buddy on Sat Mar 29, 2014 3:12 pm

Yeh, but that just moves the Q, it doesn't answer it. Why didn't they just start with that ratio in the 1st place instead of doing the magic change in t he middle??
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