Math Destroyer Question on Logs

[emminent]

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5*Log3X = 5

so divide both side by 5 then you get log3x = 1

then 10^log3x = 10^1?

3x = 10 so shouldn't x = 10/3?

answer is 3 though

this is in practice test 5 for math destroyer #16

 

[bamtori]

you can't always assume log(base10)x.
in this problem, you'd have to raise both sides of the equation to the third power to get rid of the log.

3^log3x = 3^1
x=3

 

[shyfox9p]

You have to divide both sides by 5
You are then left with Log_3 X =1
Rewrite it as 3^1 =X, X=3

 

[emminent]

oh I see so the 3 is the subscript which means I should've raised it to the 3rd power?

thanks a bunch also guys

 

[shyfox9p]

The 3 is the base.
Watch these vids: https://www.youtube.com/results?search_query=law+of+logs+profrobob
This guy breaks down the math very nicely. A lot of it is just perspective.