Calculate the net force acting on the object

[roguekiller93]

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1. Homework Statement
Calculate the net force acting on each object indicated in the following diagrams.
(diagrams attached) I am working on "B"

Homework Equations

Sine Law: sin a/a = sin b/b = sin c/ c
Cosine Law: c^2 = a^2 + b^2 -2ab*cos(c)

The Attempt at a Solution

C2 = (2W)2 + (17N)2 – 2(2)(17)Cos 45o

= 4 + 289 – 48.08326112

= 16 N
SinB/ 17 N = Sin 45 / 16 W

= 49o
∴ Net Force is 16 N (W49o N)
I am really struggling with this component of physics.I understand I got the wrong answer for the sine law because I rounded off too early in my cosine law calculations. However I am really struggling to understand how I got the wrong answer for the direction of my resultant vector. It is supposed to be 16 N [W 40 N].

 

[billy_joule]

I can't see any attachment.

 

[roguekiller93]

I can't see any attachment.

Sorry. I attached the diagrams now

 

[jedishrfu]

It seems that if you componentized the vectors then added the components and then converted the resultant vector back to angle and magnitude.

 

[roguekiller93]

It seems that if you componentized the vectors then added the components and then converted the resultant vector back to angle and magnitude.

Yes. That's the method they want us to use.

 

[jedishrfu]

So show us the i, j components of the vectors then show the components of the resultant one.