1. The problem statement, all variables and given/known data The given force F is equal to 5000N,γ=〖30〗^o and α=〖15〗^o. The moment on member 4 is to be found. The geometry of the structure was worked out separately. 2. Relevant equations To solve the problem I tried to use the Equilibrium equations which state that forces in all directions should equal to zero and also that all moments should equal to zero. 3. The attempt at a solution I tried to solve it by using equilibrium equations but force the three forces (which are equal), A, Fb and F32 resulted to zero. I solved the problem graphically and these forces did not result to be equal to zero. I solved the simultaneous equations using matrices with excel and the answers obtained are equal so I ruled out the possibility of a mathematical mistake. What am I doing wrong here? Any help would be greatly appreciated. The equations of equivalence shown below and also the working of these equations are attached.