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Topic: similar triangles
Replies: 2   Last Post: Aug 4, 1996 12:10 PM

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Howard L. Hansen

Posts: 48
Registered: 12/6/04
Re: similar triangles
Posted: Aug 1, 1996 5:46 PM
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Tim Doskoch wrote:
> We know that if two angles of one triangle are equal to two angles of
> another triangle, then the triangles are similar, and corresponding sides
> have the same ratio.
> So if we have two triangles ABC and DEF (labeled clockwise from the apex),
> where angle A = angle D and angle B = angle E then: AB/DE = BC/EF = CA/FD.
> Often, somebody will use AB/BC = DE/EF and get the same answer as if they
> used the above ratios.
> In what circumstances can you mix up the similar ratios with a correct result?
> This also begs the question, in what circumstances will you not get a
> correct result?
> Tim Doskoch
> Edmonton, Alberta
> Canada

Since we may assume BC and EF <> 0, I guess I see the two statements:


as equivalent!

AB/DE = BC/EF --> AB*EF = DE*BC --> AB*EF/BC=DE --> AB/BC = DE/EF

Howard L. Hansen
Assistant Professor of Mathematics
Western Illinois University
Macomb, IL 61455
"Good mathematics is not how many answers you know,
but how you behave when you don't know the answer."

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