severincr wrote:Two race cars A and B start simultaneously from the start and go at a constant speed on a circuit, the car had a higher speed. After a while, car A "catches up" on B at the point located 130 meters after the starting line. After a while, car A catches up with B at the point 60 meters before the start line. It looks like if the cars go on indefinitely, then there would be a time when car A catches up with B exactly on the starting line.
I assume you meant to say that A had the higher speed and that "catching up" means that A has gone a full lap further than B.
Start by assigning "names" to the missing data. Let "d" be the distance around the circuit, "u" be A's speed, and "v" be B's speed with u> v. If "t1" is the time A first catches up ("laps") B then ut1= vt1+ d. We are told that is "130 meters after the starting line so vt1= 130 and u1t= 130+ d. If t2 is the second time A laps B then ut2= vt2+ 2d. We are told that is "60 meters before the starting line". Then vt2= d- 60 and ut2= 3d- 60.
That is four equations, vt1= 130, ut1= 130+ d, vt2= d- 60, and ut2= 3d- 60. Unfortunately we have 5 unknown values, u, v, d, t1,and t2. You could, and it might be useful, solve for u, v, t1, and t2 in terms of d.
However, I am not clear what you are asking or even if you are asking a question! You say, "It looks like if the cars go on indefinitely, then there would be a time when car A catches up with B exactly on the starting line". I don't think that necessarily follows. They might meet just before the finish line on some laps and just after the finish line on another lap.