- #1

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solve for x.

With this one, I have no idea where to start. All I have even thought about doing is bringing up the 16 to make it 5^16 but that doesn't seem to help me.

- Thread starter TyErd
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- #1

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solve for x.

With this one, I have no idea where to start. All I have even thought about doing is bringing up the 16 to make it 5^16 but that doesn't seem to help me.

- #2

Mark44

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Convert one of your logs so that both logs are in the same base. Do you have a formula for converting from one log base to another?

- #3

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No i dont have a formula to do that

- #4

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the formula is:

log5(x) = log (x) / log (5)

- #5

Mark44

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Let y = log

Then x = b

So log x = log(b

And y = (log x)/(log b)

Hence log

In the third step above, you can use any log base you want. I used the common log (log

- #6

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ok thnx for the formulas, ok so i have the log base for one side which is (log10(x)) / (log10(5)) what do i do now?

- #7

Mark44

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Replace log

When you do that, what does your equation become?

- #8

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(log10(x)) / (log10(5)) = logx(5^16)

- #9

Mark44

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Instead of changing log

- #10

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so are you saying change it so it is: log5(5^16) / log5(x) = log5(x) ????

- #11

Mark44

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Yes. Now put it in the context of the original equation.

log

==> log

The numerator on the right can be simplified to just plain 16, and you can multiply both sides by log

- #12

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omg, thankyou so much! i get it finally. I wish i could think like you

- #13

Mark44

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