How Do You Calculate Forces in a Truss Without Given Angles?

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To calculate forces in a truss without given angles, start by determining the support reactions using equilibrium equations, assuming one support is pinned and the other a roller. After finding the x and y components of the reactions, analyze the joints to solve for member forces, again applying equilibrium principles. It's crucial to ensure that the forces at the joints are accurately calculated. The vertical force of 100 kN needs to be distributed based on these reactions. Proper application of these methods will help clarify the force distribution in the truss.
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Hello,

I have a test after 4 hours and I really need to know how to solve this :S
I tried my best and threw 4 pages of scratch papers already !
Please help me...
I know I am doing it wrong, I tried and tried but it did not work .. I am really frustrated I feel like I am going to fail the test -.-

The angles are not given so I have no idea how find these forces .. and the vertical force of 100Kn, how is it distributed to both sides ??!

This is all I can do until now :

http://img7.imageshack.us/img7/3943/image169g.jpg

Please help me
 
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Probably too late for your test, but always solve for the support reactions first using the equilibrium equations; I assume one support is pinned and the other is a roller support. Then, after solving for the x and y components of the reactions at the pin, and the y component of the reaction at the roller, then look at the joints to solve for the member forces, again using the equilibrium equations. Your forces at the joints are not correct.
 
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