# Rearranging log equation

• July 11th 2013, 06:21 PM
JellyOnion
Rearranging log equation
How do I solve this equation for x?

3log(10)(4x-30)=3 Note: it's log base 10

I know that the answer is x=10 but have no idea how to get there!

• July 11th 2013, 06:35 PM
Phantasma
Re: Rearranging log equation
$3\log(10)(4x-30)=3\\3(1)(4x-30)=3\\4x=31\\x=\frac{31}{4}$
I think you wrote your equation wrong.
• July 11th 2013, 06:36 PM
MarkFL
Re: Rearranging log equation
I would first divide through by 3 to get:

$\log(4x-30)=1$

Convert to exponential form:

$4x-30=10^1=10$

Now solve for $x$.