A particle starts from the origin at t = 0 with an
initial velocity of 3.0 $\widehat i m/s and moves in the
x-y plane with a constant acceleration
\left( {6\widehat i + 4\widehat j} \right)$ m/s2 . The x-coordinate of the
particle at the instant when its y-coordinate is
32 m is D meters. The value of D is :-