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Triangle Problem - Is it possible to solve this?


 
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gmatz
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PostPosted: Tue Aug 28, 2007 10:59 am    Post subject: Triangle Problem - Is it possible to solve this? Reply with quote

Is it possible to figure out the area of a triangle with sides of 4,8, and 11?
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givemeanid
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PostPosted: Tue Aug 28, 2007 11:06 am    Post subject: Re: Triangle Problem - Is it possible to solve this? Reply with quote

gmatz wrote:
Is it possible to figure out the area of a triangle with sides of 4,8, and 11?


Sides = 4, 8 and 11. Lets call them x,y and z
Perimeter = 23
1/2 (Perimeter) = s = 11.5

Area = sqrt (s(s-x)(s-y)(s-z)) = sqrt[11.5 * (11.5 - 4) * (11.5 - 8 ) * (11.5 - 11)] = 12.29

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PostPosted: Tue Aug 28, 2007 11:12 am    Post subject: thanks Reply with quote

Thanks. Real quickly, what are these relationships called?

1) 1/2 (Perimeter) = s = 11.5

2) Area = sqrt (s(s-x)(s-y)(s-z)) = sqrt[11.5 * (11.5 - 4) * (11.5 - 8 ) * (11.5 - 11)] = 12.29
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givemeanid
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PostPosted: Tue Aug 28, 2007 11:22 am    Post subject: Reply with quote

I do not recall the name of the formula. It's been a while since those math classes Smile

If you have a triangle with sides x, y and z, then the area of the triangle is sqrt{s*(s-a)*(s-b)*(s-c)} where s is half the perimeter i.e s = (x+y+z)/2.

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PostPosted: Tue Aug 28, 2007 11:27 am    Post subject: Reply with quote

thanks
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gmatz
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PostPosted: Tue Aug 28, 2007 11:39 am    Post subject: It's called Heron's Formula Reply with quote

Just looked it up on the Internet. I'm curious to know where you reviewed this (in a class)? I've never come across this problem during my studies, but just thought of it thinking it could be a problem.
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