Question 441161: how do i set this up to answer? i know i have to combine the two terms.
logbase8)3x=log(base 8)(x+5)-log(base8) (x+4)
Thanks!!!! Answer by nerdybill(7384) (Show Source):
You can put this solution on YOUR website! applying log rules:
log(base8)3x=log(base 8)(x+5)-log(base8) (x+4)
log(base8)3x=log(base 8)(x+5)/(x+4)
3x=(x+5)/(x+4)
3x(x+4)=(x+5)
3x^2+12x = x+5
3x^2+11x = 5
3x^2+11x-5 = 0
apply the quadratic formula to get:
x = {-4.076, 0.409}
we can throw out the negative solution (extraneous) leaving:
x = 0.409
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