SOLUTION: 9+log(8)-7b=12 Please solve. The answer should be -512/7 but I'm not sure how to get to that answer

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Question 1079753: 9+log(8)-7b=12
Please solve. The answer should be -512/7 but I'm not sure how to get to that answer
Found 3 solutions by Fombitz, Alan3354, rothauserc:
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
You mean log base 8 of (-7b), you would write that as, log(8,(-7b)) to avoid confusion,
log%288%2C%28-7b%29%29=3
-7b=8%5E3
-7b=512
b=-512%2F7

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
9+log(8)-7b=12
log(8)-7b = 3
7b + 3 = log(8)
b = (log(8) - 3)/7
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Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
I assume log is base 10
:
9 + log(8) - 7b = 12
:
-7b = 3 - log(8)
:
b = (log(8) - 3) / 7
:
log(8) = 3log(2) / log(10) = 3log(2)
:
b = (3log(2) / 7) - (3/7)
:
b = (3/7) * (log(2) - 1)
:
b = −2.0969 / 7
: