A car is moving along a straight horizontal road at a constant speed of 18ms^-1. At the instant when the car passes a lay by, a motorcyclist leaves the lay by, starting from rest and moves with a constant acceleration 2.5ms^-2 in pursuit of the car. Given that the motorcyclist overtakes the car T seconds after leaving the lay by, calculate the value of T, and the speed of the motorcyclist at the instant of passing the car.
The solution says to use s = d/t because of the cars constant speed which I understand, but it says "as the car and the motorcycle were level at the lay by, when the motorcycle overtakes the car, they have travelled the same distance", so equate the 2 distances each have travelled.
But I'm having trouble understanding why they move the same distance? I mean I can learn this to apply it, but I can't make sense of it. Can anyone explain it clearly? How will they have travelled the same distance and how am I supposed to know this in a question? Like what in the question indicated this? is the distance travelled by the car by s = d/t the distance travelled starting from when it passes the lay by? I'm quite confused