To find the positive intervals, we'll have:
[tex]-3x^2-18x-15>0[/tex]
1. Divide both sides by -3:
(Remember that dividing or multiplying by a negative number turns the inequality around!)
[tex]\begin{gathered} -3x^2-18x-15>0 \\ \rightarrow x^2+6x+5<0 \end{gathered}[/tex]
2. Factor the expression:
[tex]\begin{gathered} x^2+6x+3<0 \\ \rightarrow(x+5)(x+1)<0 \end{gathered}[/tex]
3. Identify the interval we're looking for:
Therefore, the function is positive in the interval:
[tex]\begin{gathered} -5
