The equation of motion of a single-degree-of-freedom system is given by

\[2 \ddot{x}+0.8 \dot{x}+1.6 x=0\]

with initial conditions \(x(0)=-1\) and \(\dot{x}(0)=2\).

(a) Plot the graph \(x(t)\) versus \(t\) for \(0 \leq t \leq 10\).

(b) Plot a trajectory in the phase plane.