SOLUTION: Find the solutions(s) to the equation 4(4^x)+127(2^x)=32

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Question 389223: Find the solutions(s) to the equation
4(4^x)+127(2^x)=32
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
4%284%5Ex%29%2B127%282%5Ex%29=32
Use a substitution,
Let u=2%5Ex, then u%5E2=%282%5Ex%29%5E2=2%5E%282x%29=4%5Ex
4u%5E2%2B127u=32
4u%5E2%2B127u-32=0
%284u-1%29%28u%2B32%29=0
Two solutions in u:
4u-1=0
4u=1
u=1%2F4
2%5Ex=1%2F4=1%2F2%5E2=2%5E%28-2%29
highlight%28x=-2%29
.
.
u%2B32=0
u=-32
2%5Ex=-32
No solution.