# How is this logx=4 done?

Sep 10, 2016

$x = 10 , 000$

#### Explanation:

If no base of the log is shown, it means it is 10.

Log form and exponential form are interchangeable.

${\log}_{a} b = c \text{ "hArr " } {a}^{c} = b$

"The base stays the same and the other two change around"

In this case, change the log form to index form:

${\log}_{10} x = 4 \text{ "hArr " } {10}^{4} = x$

$x = 10 , 000$