# StreamPlot in Mathematica

A $2\times 2$ linear ODE system can be visualized by StreamPlot in Mathematica. For example:

StreamPlot[{y, y - x}, {x, -3, 3}, {y, -3, 3}]


which gives

Or, this code:

StreamPlot[{y, -3 y - x}, {x, -3, 3}, {y, -3, 3}]


returns

Here is my question:

How can I draw a pair of eigenvectors (like arrows in this answer) in the graph?

As Öskå commented Show and Graphics is the way to go:
m = {{0, 1}, {-1, -3}};