law of cosines: two automobiles leave a city at the same time and travel along straight highways that differ in direction by 84 degrees. If their speeds are 60mi/hr and 45 mi/hr, respectively, approximately how far apart are the cars at the end of 20 minutes?

Question

law of cosines:  two automobiles leave a city at the same time and travel along straight highways that differ in direction by 84 degrees. If their speeds are 60mi/hr and 45 mi/hr, respectively, approximately how far apart are the cars at the end of 20 minutes?

campbell_st · Answer

draw a picture

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all you need to do is calculate how far each car has gone in 20 minutes, of 1/3 of a hour...

then you will have the lengths of the sides of the triangle that form the 84 degree angle.

campbell_st · Answer

|dw:1364678128670:dw|

to find c you will need the law of cosines

$$c^2 = a^2 + b^2 - 2ab \cos(C)$$

mertsj · Answer

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anonymous · Answer

thanksss !!!