Prealgebra (7th Edition)

$5^{2}$$\times$$4^{6}$
5$\times$5$\times$4$\times$4$\times$4$\times$4$\times$4$\times$4 can be rewritten in exponential form as $5^{2}$$\times$$4^{6}$, since we multiply 5 two times and 4 six times.