SOLUTION: solve the equation 4^x+2=3(2^x) by substituting 2^x=y

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Question 335549: solve the equation 4^x+2=3(2^x) by substituting 2^x=y
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
y=2%5Ex
y%5E2=%282%5Ex%29%5E2=2%5E%282x%29=4%5Ex
Substituting,
y%5E2%2B2=3y
y%5E2-3y%2B2=0
%28y-1%29%28y-2%29=0
Two solutions:
y-1=0
y=1
2%5Ex=1
highlight%28x=0%29
.
.
.
y-2=0
y=2
2%5Ex=2
highlight%28x=1%29