Respuesta :
[tex]\bf s(t)=-8-9t\implies \cfrac{ds}{dt}=0-9\implies \left. \cfrac{ds}{dt}=-9 \right|_{t=1}\implies -9[/tex]
meaning the object is slowing down, and regardless of what "t"value is, -9 is just a constant all the way.
meaning the object is slowing down, and regardless of what "t"value is, -9 is just a constant all the way.