SOLUTION: log8 (x+1) + log8 (x+3)=log8 34

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Question 333377: log8 (x+1) + log8 (x+3)=log8 34
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
log8 (x+1) + log8 (x+3)=log8 34
same as
log8 [(x+1)(x+3)] = log8 (34)
we don't need the log8, now
[(x+1)(x+3)] = (34)
FOIL
x^2 + 4x + 3 = 34
:
x^2 + 4x + 3 - 34 = 0
:
x^2 + 4x - 31 = 0
solve this using the quadratic formula
positive solution ~ 3.916