SOLUTION: log(x-4) = -2 + log(x+3)

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Question 827710: log(x-4) = -2 + log(x+3)
Found 2 solutions by jsmallt9, LinnW:
Answer by jsmallt9(3758) About Me  (Show Source):
You can put this solution on YOUR website!
What are you/we supposed to do with this???

Answer by LinnW(1048) About Me  (Show Source):
You can put this solution on YOUR website!
log%28%28x-4%29%29+=+-2+%2B+log%28%28x%2B3%29%29
log(1/100) = -2 since %2810%5E%28-2%29%29=%281%2F%2810%5E2%29%29=%281%2F100%29
so log%28%28x-4%29%29+=+-2+%2B+log%28%28x%2B3%29%29 = log%28%28x-4%29%29+=+log%281%2F100%29+%2B+log%28%28x%2B3%29%29
This solution assumes that log means log base 10.
log%28%28x-4%29%29+=+log%28%28%281%2F100%29%2A%28x%2B3%29%29%29
so x-4 = (1/100)*(x+3)
multiply each side by 100
100(x-4) = x+3
100x - 400 = x + 3
add 400 to each side
100x = x + 403
subtract x from each side
99x = 403
x = 403/99
Let's see if it works
log((x-4)) = -2 + log((x+3))
add 2 - log((x+3)) to each side
log((x-4)) - log((x+3)) = -2
rewriting the the left hand side and plugging into excel we can
verify that
log10(403/99 - 4) - log10( 403/99 + 3) = -2