3^x-1 + 3^x-2 +3^x-3=13

Question

3^x-1 + 3^x-2 +3^x-3=13

Answer 1

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Answer 2

3^(x-1) + 3^(x-2) +3^(x-3)=13
3^(x-3)*(3^2 + 3^1 +1)=13
3^(x-3)*(9+3+1)=13
3^(x-3)* 13 = 13
3^(x-3) = 1
3^(x-3) = 3^0
x-3=0
x=3

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