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  Discussion about math, puzzles, games and fun.   Useful symbols: √ ∞ ≠ ≤ ≥ ≈ ⇒ ∈ Δ θ ∴ ∑ ∫ π -

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Topic review (newest first)

bob bundy
2012-12-04 05:12:15

OK.  That'll do.



Bob

gbrad88
2012-12-04 05:05:17

Maybe if I re-write it.

3^(x+7)=6

bob bundy
2012-12-04 04:45:38

hi gbrad88,

I'd do it like this:





Unfortunately, that's where this question unravels because you'd need to go into complex number theory to sort out log(-1).

This sort of thing happens if you make up a question at random.  (And you thought it was easy for a teacher to throw some questions together)

Bob

gbrad88
2012-12-04 04:12:01

That trick makes a lot of sense, but, what about when one number cannot be the same? Like the 6 below:

3^x+7=6

bobbym
2012-12-04 01:26:14



You now have



Here is a trick to these types whenever the bases are the same




you can ignore them and just solve the equation that you get from the exponents.







gbrad88
2012-12-04 01:23:03

I'm not sure. I think I don't understand.

bobbym
2012-12-04 01:18:34

Hi;

You can convert that expression on the right to be



does that help you?

gbrad88
2012-12-04 01:15:20

Sometimes I get x = -1/3 so Im not sure whats the right way to do it. :-(

bob bundy
2012-12-03 23:58:52

hi gbrad88

Welcome to the forum.

That answer looks good to me.

smile

Bob

gbrad88
2012-12-03 23:55:15

I am solving for X below:

4^(3x+5) = 1/256


The answer I get is -3 please correct me if I am wrong and why if you can please. Much appreciated.

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