What is the Maximum Force P Applied at C Given Cable Tension Limits?

[Dfresh]

Homework Statement

Two cables are tied together at C as shown below. Knowing that the maximum tension in each cable is 800N, determine:
a) the force in P that can be applied on C
b) The corresponding value of a
Link to diagram
http://www.chegg.com/homework-help/two-cables-tied-together-c-loaded-shown-knowing-maximum-allo-chapter-2-problem-61p-solution-9780077414214-exc

Homework Equations

sine law

The Attempt at a Solution

So basically I drew a FBD, and realized that you can have a max of 800N in each rope. However, what I'm stuck on is trying to rearrange the diagram so I can solve it using the sine law. It seems I'm always having two unknown angles and one unknown side.I need some help with trying to decipher the force triangle.

 

[Chestermiller]

Who says you have to use the sine law?

Chet

 

[NascentOxygen]

what I'm stuck on is trying to rearrange the diagram so I can solve it using the sine law. It seems I'm always having two unknown angles and one unknown side.I need some help with trying to decipher the force triangle.

You could first resolve all forces into their vertical and horizontal components ...