$x$-coordinate of a particle moving along this  axis is $x=\left(2+t^2+2t^3\right)$. Here, $x$ is in meters and $t$ in seconds. Find the position from where it started its journey.

 A particle can move only along x-axis. Three pairs of initial and final positions of particle at two successive times are given 

Pair                   Initial position                    Final position 

 1                             -3m                                  +5m 

 2                             -3m                                   -7m 

 3                             +7m                                 -3m

Find the sum of magnitudes of displacement in the pairs which give negative displacement in m.