Statics Question Moment for a Truss

[baird.lindsay]

Homework Statement

I need to find the moment about G. Please ignore the question in the image.

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Homework Equations

r X F

The Attempt at a Solution

Moment about G = -(30*800) + (-300*50) + 60 A + 17.32*500 + (-17.32*500(4/5)) =0

I keep getting A= 621 N but my solution is saying 721N. I am doing something wrong, not sure what.

 

[SteamKing]

You need to look at the moment produced by both components for the 500 lb load at point I.

The reaction at A should be in lbs rather than Newtons.

 

[baird.lindsay]

Moment about G = -(30*800) + (-300*50) + 60 A + 17.32*500 + (-17.32*500(4/5)) + (-40*500(3/5)) =0

When I do that I get 821lb? I am still off...

 

[baird.lindsay]

wrong way its 20 thank you!