Or at least I think I do...

These are the two problems I have:

#1:

#2:

...so I basically just need to know what equals, and just plugging in numbers isn't very practical :( Can anyone help?

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- May 30th 2009, 04:05 PMstewardship37Need a few logarithm formulas...
Or at least I think I do...

These are the two problems I have:

#1:

#2:

...so I basically just need to know what equals, and just plugging in numbers isn't very practical :( Can anyone help? - May 30th 2009, 04:38 PMartvandalay11
take the log of both sides

but now, one of the log rules says that

so and so just divide by 4 and x=

in general though, people seem to like to reduce logs for no reason that I can see... so log4= so x=

divide by 4 and log(x-4)=4, now raise each side to a power of 10, so

so x-4=10000, and x=10004 - May 30th 2009, 05:00 PMstewardship37
Thanks man, I understand the second one, but for the first one, is x= the answer? Because when I put that into a calculator, I get , and then when I add that value into the equation

as

I get , which isn't close to 2,000... - May 30th 2009, 05:03 PMartvandalay11
when you put it in your calculator, you didn't use order of operations correctly so your calculator did this:

- May 30th 2009, 05:09 PMstewardship37
Ahhhh ok. I went back and entered it in as:

Code:`(log(2000))/(8log(2))`