SOLUTION: Solve using exponential Equations of Quadratic Type 2^x -10(2^-x) + 3 = 0

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Question 996707: Solve using exponential Equations of Quadratic Type
2^x -10(2^-x) + 3 = 0
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
2^x -10(2^-x) + 3 = 0
Multiply thru by 2^x
--> 2^(2x) + 3*2^x - 10 = 0
Sub u for 2^x
--> u^2 + 3u - 10 = 0
(u+5)*(u-2) = 0
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u = 2^x = 2
x = 1
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2^x = -5 Ignore.