SOLUTION: 2-log2x=log(x/18)

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Question 1074154: 2-log2x=log(x/18)
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+2+-+log%28+2x+%29+=+log%28+x%2F18+%29+
Convert +2+ to a base 10 log
+2+=+log%28+100+%29+
------------------------
+log%28+100+%29+-+log%28+2x+%29+=+log%28+x%2F18+%29+
+log%28+100%2F%282x%29%29+=+log%28+x%2F18+%29+
+100%2F%282x%29+=+x%2F18+
+50%2Fx+=+x%2F18+
+50%2A18+=+x%5E2+
+x%5E2+=+900+
+x+=+30+
---------------------
Only the positive square root is allowed since
any log with base 10 cannot result in a negative number
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check answer:
+log%28+100+%29+-+log%28+2x+%29+=+log%28+x%2F18+%29+
+log%28+100+%29+-+log%28+2%2A30+%29+=+log%28+30%2F18+%29+
+log%28+100+%29+-+log%28+60+%29+=+log%28+5%2F3+%29+
+log%28+100+%29+-+log%28+60+%29+=+log%28+5+%29+-+log%28+3+%29+
+2+-+1.77815+=+.69897+-+.477121+
+.22185+=+.221849+
close enough