x^2+12x<-11
add 11 both sides
x^2+12x+11<0
wht 2 numbres multiply to get 11 and add to get 12
11 and 1
(x+1)(x+11)<0
at x=-1 and x=-11
test other numbers
x=-10 gives us -9<0, true
x=-12 gives us 13<0, false
x=0 give us 0<0, false
so it is the range of numbers from -1 to -11
-11<x<-1
