## College Algebra 7th Edition

$2$
RECALL: (1) $\log_b{M}+\log_b{N}=\log_b{MN}$ (2) $\log_b{M}−\log_b{N}=\log_b{\frac{M}{N}}$ (3) $\log_b{(b^x)}=x$ Use rule (2) above to obtain: $=\log_2{(\frac{60}{15})} \\=\log_2{4}$ Write 4 as $2^2$ to obtain: $=\log_2{(2^2)}$ Use rule (3) above to obtain: $=2$