The characteristic equation of a control system is s(s2+ 6s+13)+K=0. The value of k such that the characteristic equation has a pair of complex roots with real part -1 will be :

The characteristic equation of a control system is s(s2+ 6s+13)+K=0.

1.	The characteristic equation of a control system is s(s2+ 6s+13)+K=0. The value of k such that the characteristic equation has a pair of complex roots with real part -1 will be :
A.	10
B.	20
C.	30
D.	40
Answer» C. 30