Finding the first moment with respect to an axis.

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The discussion centers on calculating the first moment of two component areas (A1 and A2) with respect to the x-axis, which passes through the centroid C of a given area. The user has determined the centroid's y-coordinate (Ybar) as 4.0833 but is unsure how to proceed with finding the first moments. A suggestion is made to break the problem into smaller parts and perform separate integrations for each area. The user expresses reluctance to tackle the tedious calculations but is open to sharing their progress for feedback. The conversation emphasizes the importance of methodical integration in solving the problem.
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Hey guys, I am having some trouble understanding this problem.

The horizontal x-axis is drawn through the centroid C of the area shown, and it divides the area into two component areas A1 and A2. Determine the first moment of each component area with respect to the x axis.

[PLAIN]http://img826.imageshack.us/img826/982/111110090100.jpg I took the origin to be at the bottom center.

For my Ybar, I got 4.0833.

I'm kind of stuck on how to go about finding the first moments.Thanks!
 
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Ugh, this problem looks tedious so I'm not actually going to do it, but I'll tell you how I'd do it. You want to split up the integrations over all the different pieces. If you start and post some work I'll try to check back and let you know how you're doing.
 

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