Chapter 8.2, Problem 20E

Find phase portraits for the systems in Problems 2 and 4. For each system find any half-line trajectories and include these lines in your phase portrait.

2. $\begin{array}{l}\frac{dx}{dt}=2x+2y\\ \frac{dy}{dt}=x+3y\end{array}$

4. $\begin{array}{l}\frac{dx}{dt}=-\frac{5}{2}x+2y\\ \frac{dy}{dt}=\frac{3}{4}x-2y\end{array}$