(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Using the method of sections, determine the force in members BD, CD, and CE of the roof truss shown in the figure

(the red line is the cutting plane and the green arrows are my assumed directions of the unknown forces)

2. Relevant equations

summation of moments=0

summation of horizontal forces=0

summation of vertical forces=0

3. The attempt at a solution

i assumed there's a reaction at F (upward), and since i didn't know its value i tried taking the moments at pt. F, N, O to make that reaction disappear. But so far, it doesn't seem like i'll be getting any unknown force anytime soon. please help! am i wrong with my assumption that there's a reaction at F? and also, i tried assuming that there's no reaction at F but i still can't find any unknown force at all.

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# Analysis of Structures (Method of Sections)

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