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## #1 2014-01-16 13:13:33

thedarktiger
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### Triangle funnes agggh

In the triangle shown, n is a positive integer, and \angle A > \angle B > \angle C. How many possible values of n are there?

theres a figure but im new so I cant post wahh
The sides are AB = 4n-9, BC = 3n+4, AC = 3n+1.
I figured out BC is the biggest and AC is second and AB is third biggest. pls help. thx a ton!!!!!

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## #2 2014-01-16 19:31:01

bob bundy
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### Re: Triangle funnes agggh

hi thedarktiger,

In any triangle with sides p, q and r

p + q > r

If you use this three times, taking a different side as r each time, then you will get inequalities involving n.

Also, the minus in the expression for AB leads to a fourth inequality.

All must be true so pick the most limiting which will give a lower bound.

Then you have the inequalities on the sides which will give an upper bound.

Bob

Last edited by bob bundy (2014-01-16 20:08:47)

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## #3 2014-01-17 19:55:46

thedarktiger
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### Re: Triangle funnes agggh

Oh thanks Im so stupid I thought something was wrong with the problem! Thx so much

Batman shows Superman his new phone. Batman-"Alfred, whats the temperature in London?"
Alfred-"Just a second, sir." Alfred turns on his iPhone."Siri, whats the temperature in London?"

## #4 2014-01-17 20:29:14

bob bundy
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### Re: Triangle funnes agggh

Oh that's not so stupid.  I worked out the triangle inequality results and totally forgot the BC > AC > AB ones.  It was only when I looked at your quadrilateral post that it occurred to me that I'd left out half the information.