Finding forces in truss members AE and AB

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Ricardo Moreno
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Homework Statement


Determine all member forces and state if they are in tension or compression, in particular I am looking for member AE and AB[/B]
Handwritten exam solution for a truss: a triangular truss with joints A, B, C, D, E and loads of 600 lb and 450 lb, with force equations and member force results written beside free-body diagrams.


Homework Equations

The Attempt at a Solution


Handwritten free-body diagram of joint B with forces FBE, FBD, FBC and FBA, followed by equilibrium equations and a derivation of FBA = -1354.28 (C) with question marks, and joint E with forces 600, 450, FED, FEB and FEA, and a derivation of FEA = -1534.45 (C).


Ok so we are supposed to redo the problems from our exam, only I can't figure out how to find the forces in member AE and AB. I am wondering if my teacher made a mistake in correcting mine...

Also is it correct that there is no x component to the reaction force at A? The pin support is not bolted to the ground and we don't use friction in these problems so I did not add an Ax force. However now that I think about it, wouldn't this mean that the truss is moving? If there is an Ax force wouldn't that change the rest of my answers that were marked as correct?
 
I figured out my mistake Fcd should be negative from diagram C. This changes some of the rest of the answers, it looks like my teacher didn't mark me off for having the sign wrong but in any case I've figured it out.