Find the area of the region bounded by $y^2 = 9x,\; x = 2,\; x = 4$ and the $x$ - axis in the first quadrant.

Question

$\begin{array}{1 1} 16-4\sqrt 2sq.units. \\8-4\sqrt 2sq.units. \\ 16-2\sqrt 2sq.units. \\ 8-4\sqrt 3sq.units.\end{array}$