# Thread: The Bearing of a Line

1. ## The Bearing of a Line

Ypsilanti, Michigan, is 60 mi due north of Bowling Green, Ohio. A helicopter leaves Bowling Green at 3 PM and travels 40 mi/h in the direction 338. When will it be closest to Ypsilanti?

2. ## Re: The Bearing of a Line

BG,Y and point of landing helcopter makes rectangular triangle. Use trigonometry

3. ## Re: The Bearing of a Line

A more common phrase would be "right triangle". But, yes, knowing the angle, the length of the hypotenuse is 60 and the near leg is 40t where t is the number of hours the helicopter is flying, you can find the length of the "opposite leg" using trigonometry.

4. ## Re: The Bearing of a Line

If I draw a right triangle, I can find that the hypotenuse through

h = 60 / (cos 22) = 65 mi (rounded)

speed = distance / time

time = 65 mi / (40 mi/h) = 1.625 hour = 98 minutes (rounded)

Due to my calculations, the helicopter will be closest to Ypsilanti at 4:38 P.M.

But the book says 4:23 P.M.

What am I missing?

Round closer

6. ## Re: The Bearing of a Line

Sorry guys, I made the hypotenuse the wrong Leg. If the hypotenuse is the 60 miles distance between the two cities then the answer will be 4:23 P.M.

My Question now is

How did we manage to make the 60 miles distance between them, is the hypotenuse?

By a
Picture

8. ## Re: The Bearing of a Line

The plane flies 22 deg east of north.It will be closest to Ypsilanti when that city is due west of planes position after it travels 64.7 miles in 1 hour 37 minutes ( 4:37 PM.) At that time Ypsilanti is 24.2 miles away

bjhopper,