# How do you solve -log x = 4.176?

Dec 7, 2015

$x \cong 6.668 \times {10}^{- 5}$

#### Explanation:

$- \log x = 4.176$
$\textcolor{w h i t e}{\text{XXX}} \Rightarrow \log x = - 4.176$

$\textcolor{w h i t e}{\text{XXX}} {10}^{- 4.176} = x$

therefore (using a calculator)
$\textcolor{w h i t e}{\text{XXX}} x = 6.668 \times {10}^{- 5}$

Remember
$\textcolor{w h i t e}{\text{XXX}} {\log}_{b} a = c$ means ${b}^{c} = a$
and
$\textcolor{w h i t e}{\text{XXX}}$the default base ($b$) for $\log$ is $10$