Plot the step response using MATLAB for the following system represented in state space, where $u(t)$ is the unit step.

\[\begin{aligned}& \begin{array}{rrrr}-3 & 2 & 0 & 0 \\\dot{x}= & -7 & 1 \\0 & x+ & 1 \\0 & 0 & -4 & 1 \\0\end{array} \\& y=\left[\begin{array}{lll}0 & 1 & 1\end{array}\right] x ; \quad x(0)=\begin{array}{c}0 \\0\end{array}\end{aligned}\]