Replace the three forces which act on the bent bar by a force-couple system at the support point A. Then determine the x-intercept of the line of action of the stand-alone resultant force R. The couple is positive if counterclockwise, negative if clockwise.
Ma = 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 MAis incorrect:
MA= (-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.
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