Find the Bearing from A to C & Angle B: Solve Here

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cbarker1
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Dear everyone,

An airplane flies 470 miles from point $A$ to point $B$ with a bearing of 25 degrees. It then flies from 250 miles from point $B$ to point $C$ with a bearing of 40 degrees. Find the distance and the bearing from A to point C.
Work

Bearing Problem.png

I understand that I need to use law of cosines for the side $b$ which is opposite of the angle $B$. But I have a hard time with find what is the angle $B$ is. I forgot many things from geometry. How to determine the angle from point $A$ to point $C$?

Thanks
Cbarker1
 
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$AC = \sqrt{470^2+250^2 - 2(470)(250)\cos(165)}$

bearing = $25^\circ + m\angle{BAC}$

$\angle{BAC}$ may be found using either the sine or cosine law
 
How did you determine the angle ABC to be 165?