I'm reviewing for my final exam so one of the practice problems is:(adsbygoogle = window.adsbygoogle || []).push({});

5= 3^(x+5)

Here's my attempt at it:

ln 5= x+5 ln 3

ln 5 / ln 3 = x+5

(ln 5 / ln 3)-5= x

1.46-5 ≈ x

-3.54 ≈ x

I checked my answer and I get 3^1.46 ≈ 4.97 so rounding it up gives me 5 since I rounded off 1.46. However when I plug this equation into Mathway it gives me an answer of -3.39. I tried figuring out why (I know if you pay a fee you can view their steps, but I don't have the money at the moment) and eventually came to the conclusion that this is how they did it:

5= 3^(x+5)

x+5 = ln 5

x = ln 5 - 5

x ≈ -3.39

But when I check their answer I get 3^1.61 ≈ 5.86

I think Mathway is wrong, but maybe I'm missing something. Which method is the correct one for solving this equation? Thanks for any help I receive.

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# Homework Help: Some Confusion with an Exponential Equation

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