Determine the centroid of the shaded area shown, which is bounded by the $x$-axis, the line $x = a$ and the parabola $y^2=kx$
![diagram](./images/705-parabolic-curve-open-right.png)
Determine the centroid of the shaded area shown, which is bounded by the $x$-axis, the line $x = a$ and the parabola $y^2=kx$