Prealgebra (7th Edition)

$12r^{8}s^{7}$
Use the product property for exponents $(a^{m} \times a^{n}=a^{m+n})$, as well as the associative and commutative property, to simplify $(-4r^{6}s^{2})(-3r^{2}s^{5})$: $(-4r^{6}s^{2})(-3r^{2}s^{5})$ =$((-4)\times (-3))(r^{6}\times r^{2})(s^{2}\times s^{5})$ =$(12)(r^{6+2})(s^{2+5})$ =$(12)(r^{8})(s^{7})$ =$12r^{8}s^{7}$