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Radar stations A and B are on an east-west line, 8.6 km apart. Station A detects a plane at C, on a bearing of 53 degree. Station B simultaneously detects the same plane, on a bearing of 323 degree. Find the distance from B to C.
That is the question. And Why can I not use cosine to find the lenth?
And I thank you in advance everyone who help me with this problem.
Hello, Judi!
What do you mean by "use cosine"?
Quote:
Radar stationsand
are on an east-west line, 8.6 km apart.
Station, on a bearing of 53°.
Station
Find the distance from
Why can I not use cosine to find the length?
Code:C
*
: * * :
: * *37°:
: * * :
: 53° * * :
: * 37° 53° *:
* - - - - - - - - - - - *
A 8.6 B
If you mean "the Law of Cosines", we can't.
. . The Law of Cosines requires two sides ... and we have only one.
If you note that, you can use cosine.
.
the east and west station should be identifed by a letter and station. I assumed that A was east and Bwest.I do not get C being 90 deg.using the bearing at A 323 and the bearing at B 53 .the relative bearing at A is 63 deg north of west. This makes Abc an isosoles triangle.BC is obtained using the cosine function.
bjh
If station A were east of station B then the bearing angles are out of phase by 180 degrees.Quote:
Originally Posted by bjhopper
Soroban's beautiful image depicts the facts.
that leaves
Thank you for your drawing. Yes, I meant by the method 2 you showed. I know I can get the answer by using either cos or sin. But is it work every single time? I have encountered the problem where cos didn't work.
please help,
Quote:
Originally Posted by SorobanHello, Judi!
What do you mean by "use cosine"?
Code:C
*
: * * :
: * *37°:
: * * :
: 53° * * :
: * 37° 53° *:
* - - - - - - - - - - - *
A 8.6 B
If you mean "the Law of Cosines", we can't.
. . The Law of Cosines requires two sides ... and we have only one.
If you note that
.