College Algebra & Trigonometry, 2018a

506 CHAPTER 11. THE LAW OF SINES THE LAW OF COSINES
Exercises 11.4
1. Two straight roads diverge at an angle of 50 ◦ . Two cars leave the intersection
at 1 pm, one traveling 60 mph and the other traveling 45 mph. How far apart
are the cars (as the crow flies) at 1:30 pm?
2. Two boats leave the same port at the same time. One travels at a speed of
40 mph in the direction N30 ◦ E and the other travels at a speed of 28 mph in the
direction S75 ◦ E. How far apart are the two boats after one hour?
N
N30 ◦ E
W
30 ◦ S75 ◦ E
75 ◦ E
S
3. The airport in Desert Junction is 350 miles from the airport in Valley Center
at a bearing of N57 ◦ E. A pilot who wants to fly from Valley Center to Desert
Junction mistakenly flies due east at 225 mph for 30 minutes before correcting
the error. How far is the plane from its destination when the pilot notices the
error? What bearing should the plane use in order to arrive at Desert Junction?
57 ◦ 350 mi
Valley Center
Desert Junction