Factor $LaTeX: \displaystyle - 30 x^{3} - 60 x^{2} + 40 x + 80$ .

Factoring out the GCF $LaTeX: \displaystyle -10$ from each term gives $LaTeX: \displaystyle -10(3 x^{3} + 6 x^{2} - 4 x - 8)$ . Grouping the first two terms and factoring out their GCF, $LaTeX: \displaystyle 3 x^{2}$ , gives $LaTeX: \displaystyle 3 x^{2}(x + 2)$ . Grouping the last two terms and factoring out their GCF, $LaTeX: \displaystyle -4$ , gives $LaTeX: \displaystyle -4(x + 2)$ . The polynomial now has a common binomial factor of $LaTeX: \displaystyle x + 2$ . This gives $LaTeX: \displaystyle -10[3 x^{2} \left(x + 2\right) -4 \cdot \left(x + 2\right)] = -10\left(x + 2\right) \left(3 x^{2} - 4\right)$ .