# Lnx-ln5=10?

Feb 13, 2018

$x = 50$

#### Explanation:

We have:

$\ln x - \ln 5 = \ln 10$

Using the result lnA=lnB=ln(A/B)# we can write:

$\ln \left(\frac{x}{5}\right) = \ln 10$

The logarithm is a $1 : 1$ function so:

$\ln A = \ln B \iff A = B$

And so we have:

$\frac{x}{5} = 10 \implies x = 50$