Finding moments Mx and My for a region bounded by an ellipse

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City88
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Hi there...
I'm not sure how to go about finding the following moments:

[tex] M_{x}= \int \int\[/tex] y dx dy
[tex] M_{y}= \int \int\[/tex] x dx dy
Where the region is bounded by the ellipse:
[tex]\frac{(x-2)^2}{16}} + \frac{(y-4)^2}{36}}[/tex] = 1

I tried this several ways. I drew the ellipse and found the bounds to be
-2 [tex]\leq y[/tex] [tex]\leq10[/tex]
-2 [tex]\leq x[/tex] [tex]\leq 6[/tex]

Then I tried integrating with those bounds, but I can't seem to get the right answers. Any help/hints would be greatly appreciated.
 
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Consider changing variables to center the ellipse around zero. eg:
u = x - 2
v = y - 4