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Help with an exponential equation please

Hi, please can someone help me with the equation

3^x-3^(2-x)=8

I believe that you have to find the same base, then set the exponents equal. It is the first stage that I am struggling with.
Thanks so much

Edward
Original post by Edwarddelve01
Hi, please can someone help me with the equation

3^x-3^(2-x)=8

I believe that you have to find the same base, then set the exponents equal. It is the first stage that I am struggling with.
Thanks so much

Edward


3^(2-x) = 3^2 multiplied by 3^-x does that help?
Original post by Edwarddelve01
Hi, please can someone help me with the equation

3^x-3^(2-x)=8

I believe that you have to find the same base, then set the exponents equal. It is the first stage that I am struggling with.
Thanks so much

Edward


Well i know that x=2 just trying to work out a way of writing that to get the answer
Original post by Muttley79
3^(2-x) = 3^2 multiplied by 3^-x does that help?


Thanks for trying, but I’m looking for a way to make the 3 and 8 the same using exponents, can you help with that bit? Thanks again
Original post by roborto1999
Well i know that x=2 just trying to work out a way of writing that to get the answer


I had used wolfram alpha to find that solution, but without pro I can’t see the steps. Can you help me with that?
Original post by Edwarddelve01
Thanks for trying, but I’m looking for a way to make the 3 and 8 the same using exponents, can you help with that bit? Thanks again


Try multiplying through by 3^x - then I think you get a quadratic.

I don't think it's what you think.

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