Two particles, $P$ and $Q$, move in the same horizontal plane.

Particle $P$ is initially at rest at the point with position vector $(5\mathbf{i}+2\mathbf{j})$ metres and moves with constant acceleration $(2\mathbf{i}+3\mathbf{j})m{s}^{-2}$.

Particle $Q$ moves in a straight line, passing through the points with position vectors $(2\mathbf{i}+3\mathbf{j})$ metres and $(6\mathbf{i}+c\mathbf{j})$ metres.

$P$ and $Q$ are moving along parallel paths.