If , , ; Find the angles A, B and C. Give your answer in degrees to at least 3 decimal places.

A=?

B=?

C=?

Printable View

- November 29th 2006, 10:42 AMqbkr21Triangle find angles
If , , ; Find the angles A, B and C. Give your answer in degrees to at least 3 decimal places.

A=?

B=?

C=? - November 29th 2006, 11:23 AMSoroban
Hello, qbkr21!

Given three sides of a triangle, you need the Law of Cosines.

You should be able to start with: .

. . and write it in the form: .

Quote:

If , find the angles

Give your answer in degrees to at least 3 decimal places.

To find angle , use: .

. . We have: .

. . Hence: .

. . Therefore: .

To find angle , use: .

. . We have: .

. . Hence: .

. . Therefore: .

To find angle , subtract and from******

. . Therefore: .

~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~

******That is,**if**you trust your answers for and

To check, we can find with: .

We have: .

Then: . . . . close enough!

- November 29th 2006, 11:39 AMqbkr21Re:
Soroban I really appreciate you help, but I already found the answers, however I need you to work you magic with the word problem I posted just before this problem.