SOLUTION: Find all real solutions x to 4^x - 2^x = 56.

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Question 1032665: Find all real solutions x to
4^x - 2^x = 56.
Found 2 solutions by Alan3354, MathTherapy:
Answer by Alan3354(69443)   (Show Source): You can put this solution on YOUR website!
Find all real solutions x to
4^x - 2^x = 56.
--------
2^(2x) - 2^x = 56
2^(2x) - 2^x - 56 = 0
Sub u for 2^x
u^2 - u - 56 = 0
(u-8)*(u+7) = 0
u = -7, u = 8
---
2^x = 8 --> x = 3
That works.
============
2^(-7) --> x = 1/128
that might work.
Answer by MathTherapy(10552)   (Show Source): You can put this solution on YOUR website!

Find all real solutions x to
4^x - 2^x = 56.
Duplicate post. Why post the same problem twice? You were not happy with the solution for 1032298? 

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