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## Homework Statement

You are given truss ABC. In joint C there is a horisontal force F(13,2kN). a is the measurement between A and B, and b is the measurement between A and C. Calculate forces Nac and Nbc.

## Homework Equations

ƩMa=0

ƩFy=0

ƩFx=0

## The Attempt at a Solution

My main problem is that I don't see where to start in order to eliminate some of the unknowns.

I first tried to calculate the angle at joint C by taking invers tan 2,8/5,4 - which gave me an angle of 44 degrees.

I then looked at joint C and tried the method of joints. Which gave me:

ƩFy= 0 --> -AC*sinv-BC*sinv=0

ƩFx=0 --->F-AC*cosv-BC*cosv=0

No way to eliminate unknowns, so no go.

I then looked at the construction as a whole and started with calculating moment in A:

ƩMa=0--> By*2,8=0

ƩFx=0 --> F-Ax+Bx...And I guess forces on the beams would come into play here as well, but that only gives me more unknowns. The same would happen with ƩFy=0, so I don't think this is the way to go either.