Question 32904
kČ+10k+9 is <0
kČ+9k+k+9<0
k(k+9)+ (k+9)<0
(k+1)(k+9)<0
(k+1)<0 or (k+9)<0
therfore k< -1 or k< -9
range of k is in between -9 and -1 
-9 < k < -1