Displacement = Velocity * time
If an object starts at position P0,
with velocity V,
after t time units, its position P(t) is:
P(t) = P0 + V * t
Note: choice of units is arbitrary, as long as things are consistent.
e.g. use meters for distance, seconds for time, and meters/second for velocity.
Don't try to combine meters/second with miles/hour, for instance.