Help finding the critical values of α where the qualitative nature of the phase portrait for the system changes?

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I was asked to solved for the eigenvalues in terms of α for 2X2 matrix and so i did and my answer was marked as correct. Then I was asked to solve for this:

The roots are complex when?

There is a saddle point for?

The equilibrium point is a stable node where?

I tried solving the problem by finding values which would give me 1 and zero for the eigenvalues and got the values of -24/11, -25/11 and -26/11 but the were all wrong. How would i solve for these three questions? can someone walk me through the steps?

The eigenvalues in terms of α are:

$r = -1 + \dfrac{\sqrt{100 + 44 \alpha}}{2}$

$r_2 = -1 - \dfrac{\sqrt{100 + 44 \alpha}}{2}$