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!

thx in advance

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- Jul 11th 2013, 06:21 PMJellyOnionRearranging 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!

thx in advance - Jul 11th 2013, 06:35 PMPhantasmaRe: Rearranging log equation
$\displaystyle 3\log(10)(4x-30)=3\\3(1)(4x-30)=3\\4x=31\\x=\frac{31}{4}$

I think you wrote your equation wrong. - Jul 11th 2013, 06:36 PMMarkFLRe: Rearranging log equation
I would first divide through by 3 to get:

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

Convert to exponential form:

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

Now solve for $\displaystyle x$.