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Homework Statement
Replace the three forces which act on the bent bar by a forcecouple system at the support point A. Then determine the xintercept of the line of action of the standalone resultant force R. The couple is positive if counterclockwise, negative if clockwise.
Homework Equations
M_{a} = Sum of the individual moments
The Attempt at a Solution
For calculating R:
R = 2140 lb j  1280 lb j + 730sin(25) i + 730cos(25) j
= 308.511 i  2758.4 j
I know my R is correct, but my M_{A}is incorrect:
M_{A}= (2140)(4)  (1280)(4 + 3.6cos(25) + 3.4) + (730)(3.6cos(25) +4)
= 16906.5 lb ft
For the x intercept I then:
(xi + yj) X (308.511 i  2758.4 j)
= 2758.4c + 308.511y = 16906.5
Solving for x I got:
x = 0.111844y + 6.1291
hence the x intercept should be 6.1291 but it says its wrong.
Any suggestions?
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