Factor LaTeX: \displaystyle 5 x^{3} + 9 x^{2} - 5 x - 9 .

Grouping the first two terms and factoring out their GCF, LaTeX: \displaystyle x^{2} , gives LaTeX: \displaystyle x^{2}(5 x + 9) . Grouping the last two terms and factoring out their GCF, LaTeX: \displaystyle -1 , gives LaTeX: \displaystyle -1(5 x + 9) . The polynomial now has a common binomial factor of LaTeX: \displaystyle 5 x + 9 . This gives LaTeX: \displaystyle x^{2} \left(5 x + 9\right) -1 \cdot \left(5 x + 9\right) = \left(5 x + 9\right) \left(x^{2} - 1\right) . The quadratic factor can be factored using the difference of squares to give LaTeX: \displaystyle \left(x - 1\right) \left(x + 1\right) \left(5 x + 9\right).