# Equilibium in 3D

1. Feb 9, 2009

### jimbo71

1. The problem statement, all variables and given/known data
I am having difficulty with the algebra for a particular statics problem. A weight is hanging down and three strings and a spring support it in equilibrium. FBA is the force acting along the BA vector. I must solved for alpha in terms of FBA. There is also a spring force acting on the weight
how do i solve for FBA?
FBAcos(10/FBA)=10(((10-5cos(10/FBA))-5)

2. Relevant equations

3. The attempt at a solution

2. Feb 9, 2009

### Tom Mattson

Staff Emeritus
I'm afraid there's not nearly enough in your post for me to even draw this out accurately. Would it be possible for you to scan the problem statement and attach the image to your next post?

3. Feb 11, 2009

### jimbo71

I dont need help setting up or understanding how to solve the original problem. I just cannot figure out how to solve this equation FBAcos(10/FBA)=10(((10-5cos(10/FBA))-5)

4. Feb 11, 2009

### HallsofIvy

Staff Emeritus
That reduces slightly (x+ 10)cos(10/x)= 50, with x= FBA but there is no "algebraic" way to solve that equation for FBA. You will need to use some kind of numerical solution.