SOLUTION: 2^2x+1-15(2^x)=8

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Question 993994: 2^2x+1-15(2^x)=8
Answer by anand429(138) About Me  (Show Source):
You can put this solution on YOUR website!
2%5E%282x%2B1%29-15%282%5Ex%29=8
=>2%2A2%5E%282x%29-15%282%5Ex%29=8
=> 2y%5E2-15y-8=0 (Taking 2^x =y)
=> %28y-8%29%282y%2B1%29=0
=> y=8 or y=-1%2F2
=>2%5Ex=8 or 2%5Ex=+-1%2F2
=> x=3 (Since 2^x can not be negative.)