## Algebra 2 Common Core

$-2$
Recall the power property of logarithms (pg. 462): $\log_b{m^n}=n\log_b{m}$ We rewrite the values in the form of $m^n$, so that we can apply the power property: $\log_{2}{4}-\log_2{16}\\ =\log_{2}{2^2}-\log_2{2^4}\\ =2\log_{2}{2}-4\log_2{2}\\ =2\times1-4\times 1\\ =2-4\\ =-2$ We also used the fact that $\log_{2}{2}=1$ (because $2^1=2$).