Question 143920
Solve 4^x-6=16^x
4^(x-6) = 4^(2x)
x-6 = 2x
x = -6
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and 
e^-2x=0.3 
Take the natural log of both sides to get:
-2x = ln0.3
-2x = -1.20397...
x = 0.60198...
cheers,
Stan H.