SOLUTION: Solve for x algebraically: 5^(2x)- 4(5)^x=-3

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Question 133154: Solve for x algebraically: 5^(2x)- 4(5)^x=-3
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
5^(2x)- 4(5)^x=-3
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(5^x)^2 -4(5^x) +3 = 0
Let 5^x = w
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w^2-4w+3 = 0
(w-3)(w-1) = 0
w = 3 or w = 1
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Replace w by 5^x:
5^x = 3 or 5^x = 1
x = log(3)/log(5) or x = 0
x = 0.682606... or x = 0
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Cheers,
Stan H.