SOLUTION: log base 10(x+4)=2+log base 10 x-log base 10 20

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Question 1126425: log base 10(x+4)=2+log base 10 x-log base 10 20
Found 2 solutions by josgarithmetic, greenestamps:
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
log%28%28x%2B4%29%29=2%2Blog%28%28x%29%29-log%28%2820%29%29
log%28%28x%2B4%29%29%2Blog%28%2820%29%29-log%28%28x%29%29=2
log%28%28%2820%29%28x%2B4%29%2Fx%29%29=2
log%28%28%2820x%2B80%29%2Fx%29%29=2

Base given was 10.
Put into exponential form,
%2820x%2B80%29%2Fx=10%5E2
20x%2B80=100x
80=80x
highlight%28x=1%29

Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!


Change the "2" to "log base 10 of some number": 2 = log base 10 of 100.

Since the problem is in the standard base 10, we don't need to keep writing "base 10". Then



Then, since log(A)=log(B) means A=B,

x%2B4+=+5x
4x+=+4
x+=+1