A rocket moves with a velocity: v $=$ At $+$ B

where A $=15\mathrm{.}0$ m$/$s$^2,$ B $=8\mathrm{.}0$ m$/$s$,$ and t is the time in seconds.

At time t $=2\mathrm{.}0$ s$,$ the rocket is located at position x $=50\mathrm{.}0$ m$.$ Write an equation for the rocket's position at any time.

Please give an explanation