Two ships leave a harbor at the same time.

$\begingroup$

Sounds like a bar joke is about to begin, I have a question on an answer in my homework. I understand the concept of directions/angles. I for some reason stumped on this one question.

Here is the full question:

Two ships leave a harbor at the same time. One ship travels on a bearing S13°W at 10 miles per hour. The other ship travels on a bearing N75°E at 8 miles per hour. How far apart will the ships be after 22 ​hours?

I have made a half compass N and S poles. This isn't the prettiest thing in the world but this is kinda how I comprehended it, looks incredibly wrong(enjoy the galaxy paint):

two ships triangle attempt

$\endgroup$ 2

2 Answers

$\begingroup$

enter image description here

From the above diagram $13^{\circ}$ is the angle travelled towards west and $75^{\circ}$ is the angle travelled towards East.

$220$ is the distance travelled towards west in $22$ hours.

$176$ is the distance travelled towards East in $22$ hours.

Now we need to find $x$ and you can use Law of Cosines.

$$x^2=(220)^2+(176)^2-2(220)(176)\cos(118^{\circ})$$Solve for $x$ and that will be your answer.

$\endgroup$ 2 $\begingroup$
  1. Calculate the angle between their paths
  2. Calculate the length of each path
  3. Form a triangle and use the law of cosines for the unknown side (the distance between them)
$\endgroup$

Your Answer

Sign up or log in

Sign up using Google Sign up using Facebook Sign up using Email and Password

Post as a guest

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

You Might Also Like