Bearings Help!!! (1 Viewer)

[lookoutastroboy]

this is a question that i really cannot do (how do you find out the bearing between two objects if neither one of them starts at the origin?)

A ship is 5 nautical miles from a wharf on a bearing of 321 degrees and a lighthouse is 11.5 nautical miles from the wharf on a bearing of 231 degrees. Find the bearing of the ship from the lighthouse (to nearest minute)?





Special thanks in advance, loookoutadtroboy

 

[shady145]

draw a diagram and then use pythag
321-231=90*
tan*=11.5/5
@=73*53*
from the lighthouse the bearing is 73*53*

 

[annabackwards]

Basically the wharf is the origin or starting point in this example.

I dunno what shady145 got but i got a different answer. Maybe he found the wrong angle...

It says from the lighthouse so the bearing is found with the lighthouse at its "origin"

Anyway, i hate doing math on the computer to i scanned my working out for you

Here it is: http://i238.photobucket.com/albums/ff62/annabackwards/mathanswer.jpg

By the way, Beta = 39 as 270- 231 = 39 and beta = 39 (alternate angles on parallel lines)

 

[lookoutastroboy]

Basically the wharf is the origin or starting point in this example.

I dunno what shady145 got but i got a different answer. Maybe he found the wrong angle...

It says from the lighthouse so you start there.

Anyway, i hate doing math on the computer to i scanned my working out for you

Here it is: http://i238.photobucket.com/albums/ff62/annabackwards/mathanswer.jpg

By the way, Beta = 39 as 270- 231 = 39 and beta = 39 (alternate angles on parallel lines)

yup, the answer is in fact N 27 degrees, 30 minutes , thanks both of you for your great help , i wouldnt have got it otherwise,

 

[gurmies]

= 27° 30' 5.16"

If this is correct, i'll try post up solution..

[Edit] Never mind, I see people have beaten me to it

 

[annabackwards]

yup, the answer is in fact N 27 degrees, 30 minutes , thanks both of you for your great help , i wouldnt have got it otherwise,

Awesome ^^

I hope i made some sense there... i'm a bit lazy now so i skipped showing all of my working out XD

 

[shady145]

o haha yea wrong angle, trying to do visuals in your head can get a lil confusing
come to drawing it i see i didnt even do nething really except find an angle in the triangle which 2 other angles are needed for the answer. awell

 

[lookoutastroboy]

oy i just realised something with annabackward's solution, isnt the value of the beta meant to be 31 degrees (231 -180)?

 

[lookoutastroboy]

my bad, realised my error, dont mind me