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Hambone
06-27-2011, 05:57 AM
7(2.1)^3x = 2(4.5)^x

I've looked at other resources (my textbook is a joke) and they all seem to give simpler examples where the exponent - if x at all - will only be on one side. Would I divide one of the coefficients first. Take the log of both sides? I don't even know where to start. :confused:

rubah
06-27-2011, 07:13 AM
OH GOD MY COGNITIVE GEARS ARE A RUMBLIN'

anyway, don't have to divide, just take the log of each side; dividing first would net you the same result, which is
ln(7) + 3xln(2.1) = ln(2) + xln(4.5)

then just solve for x. this takes advantage of the log rule that says ln(x*y) = ln(x)+ln(y)

(I got like -1.73etc)

Hambone
06-28-2011, 03:05 AM
Ahh, thanks. I always forget to look at these problems from the perspective of the log properties.