SOLUTION: if 4^x+4^x-1=10 find x

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Question 746492: if 4^x+4^x-1=10 find x
Found 2 solutions by tommyt3rd, Alan3354:
Answer by tommyt3rd(5050) About Me  (Show Source):
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
if 4^x+4^x-1=10 find x
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I think you mean
if 4^x+4^(x-1) = 10 find x
Use parentheses to make things unambiguous.
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if 4^x+4^x-1=10 find x
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Sub y for 4^(x-1)
4y + y = 10
y = 2
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4^(x-1) = 2
(x-1)*log(4) = log(2)
x = 1 + log(2)/log(4)
x = 1.5