How to find the gain K at break-in and breakaway points of a Root Locus Plot on MATLAB

Question

I would like to know how to find the break-in and breakaway points of a transfer function using root locus on MATLAB.

MATLAB Code:

f = tf(poly([4 3]),poly([-1 -2]))
rlocus(f)

But how to get the K value where the break happens?

Answer 1

s=tf('s');
GH=((s-4)*(s-3))/((s+1)*(s+2));
rlocus(GH)