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**Wolvenmoon** Okay...second, follow up problem ( will edit first post with this one too ):

"What bearing and airspeed are required for a plane to fly 400 miles due north in 2.5 hours if the wind is blowing from a direction of 347 degrees at 16 mph ) "

(all bearings are assumed due north

Okay, when sketching this I put 160 directly on the Y axis, then had it show me the example problem, which says to subtract 180 degrees from 347 to get angle C. Why am I doing this?

Then later on in the problem, after an application of the law of cosines to find side c is 176 MPH, I use the law of sines to get angle A, which is approximately 1 degree. I have no clue what to do with this answer so I go through the example and it tells me to subtract that from 360 to get 359 degrees. Why?