Factor $LaTeX: \displaystyle - 9 x^{3} - 10 x^{2} - 36 x - 40$ .

Factoring out the GCF $LaTeX: \displaystyle -1$ from each term gives $LaTeX: \displaystyle -(9 x^{3} + 10 x^{2} + 36 x + 40)$ . Grouping the first two terms and factoring out their GCF, $LaTeX: \displaystyle x^{2}$ , gives $LaTeX: \displaystyle x^{2}(9 x + 10)$ . Grouping the last two terms and factoring out their GCF, $LaTeX: \displaystyle 4$ , gives $LaTeX: \displaystyle 4(9 x + 10)$ . The polynomial now has a common binomial factor of $LaTeX: \displaystyle 9 x + 10$ . This gives $LaTeX: \displaystyle -1[x^{2} \left(9 x + 10\right) +4 \cdot \left(9 x + 10\right)] = -\left(9 x + 10\right) \left(x^{2} + 4\right)$ .