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Topic: got different answer than one in book
Replies: 1   Last Post: Mar 1, 2010 1:15 AM

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Posts: 15
From: California
Registered: 6/29/09
Re: got different answer than one in book
Posted: Mar 1, 2010 1:15 AM
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On February 28, 2010, nancy wrote:

> The problem states: In Triangle ABC,m<B = 120, m<A =
> 55, and D is the point on line AC such that line BC
> bisects <ABC. Which is the longest side of triangle
> ABD? I drew a diagram of a triangle I labeled ABC.
> I drew a line from <B and labeled the end of it D.
> C is obviously the largest angle,so the side opposite
> it should be the longest side. I thought it should be
> AD, but the book said it was AB. Why would that be?
> Motherof8


Suspect a typo in the stated problem:

"such that line BC bisects <ABC" should read

"such that line BD bisects <ABC"

Triangle ABC, having 2 angles adding up to 175
means that <C must be 5, the smallest. Triangle
ABD consists of <A = 55, half of <ABC (= 60) and
<BDA. Again, since the interior angles of a
triangle must add up to 180, that leaves
<BDA = 65, the largest. So the side opposite
it, AB, is longest. However, line AB is the
shortest side of triangle ABC.

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