(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Find the mass m of the pyramid with base in the plane z = 9 and sides formed by the three planes y = 0 and y - x = 5 and 6x + y + z = 28, if the density of the solid is given by δ(x,y,z) = y.

2. Relevant equations

3. The attempt at a solution

This problem is driving me insane. It takes me about 45 minutes of algebra to evaluate this incorrectly set up integral..

I integrated y in the order dz dy dx, limits, respectively:

9 to 28-6x-y

0 to 5+x

0 to 2

Is that correct? I don't really know how to get the limits for x.. this is so hard to picture in my mind!

To get 2, I solved the system 6x + y + z = 28 with z = 9 and y = 5 + x, and for 0, I just guessed.

Help please!

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# Homework Help: Mass using triple integrals

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