Help with summing the moments in statics

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The discussion revolves around the confusion in summing moments at two different points, A and B, in a statics problem. The user is struggling to reconcile the results obtained from summing moments at both points, leading to different reactions (rah and rbh). Key insights highlight that the sum of horizontal forces must equal zero and should account for all horizontal components, regardless of the moment point chosen. Additionally, establishing a separate equation for vertical forces is necessary for a complete analysis. Understanding these principles is crucial for correctly solving statics problems.
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Homework Statement


I need to sum the moments on a and b but when i sum them at b the number I get doesn't work when I check and sum them at a.

Homework Equations

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(-200x4)+(-60x2.5)+(-60x2.5)+(rbhx10)=rbh=110

(200x6)+(-60x2.5)+(-60x2.5)+(rahx10)=-90

Sum horz=0=110+200+rah if moments summed at A
Rah=-310

Sum horz=0=-90+200+rbh if moments summed at B
Rbh=-110

Why are they not the same I don't understand
 
thekrustyone said:
(-200x4)+(-60x2.5)+(-60x2.5)+(rbhx10)=rbh=110
Should be rah
 
thekrustyone said:
Sum horz=0=110+200+rah if moments summed at A
The sum of the horizontal forces must be the sum of ALL horizontal forces. There are 3 forces with horizontal components. This sum equals zero and has nothing to do with the point about which you choose to sum moments.

Another forces equation can be obtained by setting the sum of ALL vertical forces = 0
 

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