Answer
$4$ units/sec
Work Step by Step
Here, $(2s)\dfrac{ds}{dt}=[(2x) \dfrac{dx}{dt}+(3x^2) \dfrac{dy}{dt}]$
$s=\sqrt {(3)^2+(3)^3}=6$
Plug $\dfrac{ds}{dt}=11units/sec$
Then , we have
$\dfrac{dx}{dt}=(\dfrac{ds}{dt})(\dfrac{2s}{2x+3x^2})$
This implies that
$\dfrac{dx}{dt}=\dfrac{(2)(6)}{(2)(3)+(3)(3)^2}=4$ units/sec