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solving exponential equations: -6^(4x - 5) = -20  TOPIC_SOLVED

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solving exponential equations: -6^(4x - 5) = -20

Postby sully039 on Mon Jul 25, 2011 8:43 pm

So I'm stuck on this question: -64x-5=-20
I know that I'm supposed to use log to isolate the variable, but I can't take the log of a negative number.
Could someone please explain how to solve this in steps? :confused:

Thanks
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Re: solving exponential equations: -6^(4x - 5) = -20  TOPIC_SOLVED

Postby little_dragon on Mon Jul 25, 2011 11:12 pm

sully039 wrote:So I'm stuck on this question: -64x-5=-20
I know that I'm supposed to use log to isolate the variable, but I can't take the log of a negative number.

no but U can multiply thru by -1 to get rid of the negs on both sides
then do logs
:wave:
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Re: solving exponential equations: -6^(4x - 5) = -20

Postby sully039 on Tue Jul 26, 2011 1:07 am

Oh...right :oops: I feel kinda dumb now lol

Thanks for the help
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