## Algebra: A Combined Approach (4th Edition)

Appendix A - Practice : 13 (Answer) $(x + 4)(x - 4)$ $= x^{2} – 16$
Appendix A - Practice : 13 (Solution) $(x + 4)(x - 4)$ $= x^{2} – 4^{2}$ (Product of sum and difference of two terms) $= x^{2} – 16$