Equivalent force and couple moment

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marsupial
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Homework Statement


I will post a photo of the question in the thread once I've created it. I have found the magnitude and angle of the resultant force, but I am unsure of how to proceed. I find moments and couples confusing.

Homework Equations



$$\vec M = \vec r \times \vec F$$

The Attempt at a Solution



So, to find ##\vec r## I chose a point on ##\vec F## (1, 0.8069) (call it C), and calculated ##r_{BC}##: ##r_{c} = -7i + 0.8069j##. Then I took the cross product of r and F, and got 41.58kN.m, but this is incorrect, and I am stumped.
 
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i found the answer, thanks.