1. The problem statement, all variables and given/known data Find the volume V of the solid bounded by the graph x2+y2=9 and y2+z2=9 2. Relevant equations 3. The attempt at a solution When I started this problem, I thought it was a perfect sphere with the center points (0, 0, 0). And then I thought, "Why do I need calculus, it's 4/3*pi*r3, right?" So I plugged it into the calculator and got 36pi. Then I thought... maybe that's not such a good idea. Then I thought about doing the shell method, and multiplying it by two. But this is all under the assumption that I'm working with a sphere. The hint I was given is to do it in the first octant, then multiply by 8. I thought about integrating the areas I was given (xy, yz), and then cross them to get xz, but after that, I'm lost. Do I multiply all of them to get the area, and then multiply by 8? I am currently in the chapter dealing with multiple integrals and polar integration, if that is any help.