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## Homework Statement

Solve triangle having indicated sides and angles.

a=6

b=9

C=45degrees

## Homework Equations

Law of Cosines

Law of Sines

## The Attempt at a Solution

I did c^2=9^2+6^2-(2*9*6*Cos45 degrees)

c=6.37

...

Then I did 6.37/cos45 =9/SinB.. That proportion would give me 87.5 derees.. However, the back of my book and..

http://www.trig.ionichost.com/ [Broken]

Says that B is 93.3 degrees..

However, if I were to approach the problem by solving for A (smallest angle) instead of immediately to B (mid sized).. I would get 41.7 degrees..

Then I could do B=180-A-C..or 93.3 degrees..

But still, if I set up a ratio of sin41.7degs/6=sinB/9, that's not 93.3, or 87.5, but 86.2

I'd like to know why math is stupid. And next time, what I should do to know whether 93.3, 87.5, or 86.2 would be the right answer.

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