Appendix A - Review - A.4 Factoring Polynomials - A.4 Assess Your Understanding - Page A41: 132

$2(4x + 5)^2 (5x + 1)(50x+31)$

We factor out $2(4x + 5)^2 (5x + 1)$ and distribute, combine like terms, and simplify as follows: \begin{align*} &3(4x + 5)^2 \cdot 4(5x + 1)^2 + (4x + 5)^3 \cdot 2(5x + 1) \cdot 5\\ &=2(4x + 5)^2 (5x + 1)[6(5x+1)+5(4x+5)]\\ &=2(4x + 5)^2 (5x + 1)[30x+6+20x+25]\\ &=2(4x + 5)^2 (5x + 1)(50x+31) \end{align*}