The volume of the solid of revolution created by rotating the region enclosed by the two curves $y = \sqrt { x } , y = \sqrt { - x + 10 }$ and the $x$-axis around the $x$-axis is $a \pi$. Find the value of $a$. [3 points]
The volume of the solid of revolution created by rotating the region enclosed by the two curves $y = \sqrt { x } , y = \sqrt { - x + 10 }$ and the $x$-axis around the $x$-axis is $a \pi$. Find the value of $a$. [3 points]