Factor $LaTeX: \displaystyle - 20 x^{3} + 4 x^{2} - 25 x + 5$ .

Factoring out the GCF $LaTeX: \displaystyle -1$ from each term gives $LaTeX: \displaystyle -(20 x^{3} - 4 x^{2} + 25 x - 5)$ . Grouping the first two terms and factoring out their GCF, $LaTeX: \displaystyle 4 x^{2}$ , gives $LaTeX: \displaystyle 4 x^{2}(5 x - 1)$ . Grouping the last two terms and factoring out their GCF, $LaTeX: \displaystyle 5$ , gives $LaTeX: \displaystyle 5(5 x - 1)$ . The polynomial now has a common binomial factor of $LaTeX: \displaystyle 5 x - 1$ . This gives $LaTeX: \displaystyle -1[4 x^{2} \left(5 x - 1\right) +5 \cdot \left(5 x - 1\right)] = -\left(5 x - 1\right) \left(4 x^{2} + 5\right)$ .