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#1 2016-09-05 01:09:05
- Srikantan
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- From: Tanjore
- Registered: 2016-06-04
- Posts: 42
perimeter
A Circle of rafius 4 cm inscribed in a triangle touches the sides AB,BC , CA a D,E,F respectively. If AD , BE & CF are rhree consecutive integers find the perimeter of the triangle.
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#2 2016-09-05 04:41:51
- thickhead
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- Registered: 2016-04-16
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Re: perimeter
Last edited by thickhead (2016-09-05 05:30:34)
{1}Vasudhaiva Kutumakam.{The whole Universe is a family.}
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#3 2016-09-05 05:13:52
- Srikantan
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- From: Tanjore
- Registered: 2016-06-04
- Posts: 42
Re: perimeter
Can you help with diagram please?
N=6 and perimeter is 42
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#4 2016-09-05 12:50:56
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: perimeter
What diagram?
There is another way using geometry:
yields n = 6 and s = 21, so the perimeter is 42.
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#5 2016-09-06 03:43:20
- Bob
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Re: perimeter
hi Srikantan
Here is a diagram that may help. It is not an accurate representation of the problem.
You will find some properties of the inscribed circle here: http://www.mathisfunforum.com/viewtopic … 21#p368021
Triangles AGD and AGF are congruent so AD = AF. Similar results hold for the other line segments making up the perimeter. Angle ADG, for example, is 90 so trigonometry is possible as thickhead has done in post 2.
So once you have 'n' the perimeter can be quickly calculated.
Bob
Children are not defined by school ...........The Fonz
You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you! …………….Bob 
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#6 2016-09-06 03:56:56
- thickhead
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Re: perimeter
It is better to name the center of the circle as "I".
{1}Vasudhaiva Kutumakam.{The whole Universe is a family.}
(2)Yatra naaryasthu poojyanthe Ramanthe tatra Devataha
{Gods rejoice at those places where ladies are respected.}
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#7 2016-09-06 04:08:48
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: perimeter
I am locking the thread now to protect it.
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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