Answer
$x=25$
Work Step by Step
We are asked to solve:
$\log{4x}=2$
Recall the definition of a logarithm (pg. 451):
$\log_{b}{x}=y$ iff $b^y=x$
Applying this definition to our equation (with $b=10, y=2, x=4x$), we get:
$10^2=4x$
$100=4x$
$x=\frac{100}{4}$
$x=25$
