Two particles move along an x axis. The position of particle 1 is given by x = 8.00t² + 7.00t + 6.00 (in meters and seconds); the acceleration of particle 2 is given by a = -10.0t (in meters per seconds squared and seconds) and, at t = 0, its velocity is 24.0 m/s. When the velocities of the particles match, what is their velocity?