Simple Equivalence Problem- help please (First Year Statics)

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The discussion revolves around solving a statics problem involving two forces, F1 and F2, and determining the line of action for the resultant force. The user initially miscalculated the intersection point, arriving at an incorrect value of x = 2.19 instead of the correct answer of x = 2.34. Key advice includes considering the moments about a chosen axis and ensuring all moments are accounted for in the calculations. The user ultimately realized the mistake was due to not summing all the moments correctly. This highlights the importance of thorough moment analysis in statics problems.
lc99
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Okay, so i am having severe problems with figuring out what i did wrong...
I am given : F1 = 250 and F2 = 90
The correct Force result is = 245 i +228 j with magnitude of 335 .
The moment given is 500 lb*ft.

I am trying to find the result's line of action that would intersect member BC measured from B. The correct answer is x = 2.34.

But, i got some other answer. I found the location of intersection with M = Fy * x (Fy because Fx would be 0 along the x-axis).

so , 500 = 228*x --> x = 2.19?? Which is wrong :(
 

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lc99 said:
The correct Force result is = 245 i +228 j with magnitude of 335 .
Ok, but that also has, of itself, a line of action. It would pass through the point of intersection of the lines of action of F1 and F2. You have not factored this in.
The safer approach is to pick an axis and find the sum of miments about it from the applied forces. Then find the line of action of the resuktant that yields the same moment.
 
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haruspex said:
Ok, but that also has, of itself, a line of action. It would pass through the point of intersection of the lines of action of F1 and F2. You have not factored this in.
The safer approach is to pick an axis and find the sum of miments about it from the applied forces. Then find the line of action of the resuktant that yields the same moment.
Thanks! I figured out that i didn't add up all the moments
 

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