SOLUTION: how do i solve 2logx+log4=2

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Question 855096: how do i solve
2logx+log4=2
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
The trick is to express +2+ as a log
+2+=+log%28+100+%29+
+2%2Alog%28+x+%29+%2B+log%28+4+%29+=+2+
+2%2Alog%28+x+%29+%2B+log%28+4+%29+=+log%28+100+%29+
+log%28+x%5E2+%29+%2B+log%284%29+=+log%28+100+%29+
+log%28+4x%5E2+%29+=+log%28+100+%29+
+4x%5E2+=+100+
+x%5E2+=+25+
+x+=+5+
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check:
+2%2Alog%28+x+%29+%2B+log%28+4+%29+=+2+
+2%2Alog%28+5+%29+%2B+log%28+4+%29+=+2+
+2%2A.69897+%2B+.60206+=+2+
+1.39794+%2B+.60206+=+2+
+2+=+2+
Ok
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Also note that +x+=+-5+ the other square root
doesn't work because +log%28%28+-5+%29%29+ makes no sense.
You can't raise base 10 to an exponent and
get a negative result.