Triple integral bounded above by $z=6-x^2-y^2$ and below by $z=\sqrt{x^2+y^2}$

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Plot of the two function

Triple integral bounded above by $z=6-x^2-y^2$ and below by $z=\sqrt{x^2+y^2}$ in addition: $x+y\geq0$

As I understand it I should find the volume of a kind of ice cream cone(see image)

My setup in cylindrial coordinates:

$\int\int\int\,r\,dz\,dr\,d\theta$

$0 \leq r \leq 2$ (as the intersection between the two plots are the unit cirle with radius $2$

the integral of $dz$ with limits from $z= \sqrt{x^2+y^2}$ to $z=6-x^2-y^2$

Integrate the angle $\displaystyle{-\frac{\pi}{4}\leq\theta\leq\frac{3\pi}{4}}$.

I can integrate this, but can't get the correct answer I am told in the problem to integrate the region

Triple integral $xdV$.

$dV$ must be $r\,dz\,dr\,d\theta$ but why the $x$ there?