# How do you solve for x in y=(0.8)(0.84)^x?

Apr 21, 2016

$x = \frac{\ln \left(\frac{y}{0.8}\right)}{\ln} \left(0.84\right)$

#### Explanation:

$\frac{y}{0.8} = {\left(0.84\right)}^{x}$

$\ln \left(\frac{y}{0.8}\right) = \ln {\left(0.84\right)}^{x}$

$\ln \left(\frac{y}{0.8}\right) = x \ln \left(0.84\right)$

$\frac{\ln \left(\frac{y}{0.8}\right)}{\ln} \left(0.84\right) = x$