SOLUTION: 2 log(x+6) = log36 +log4 what does x=

Algebra ->  Logarithm Solvers, Trainers and Word Problems -> SOLUTION: 2 log(x+6) = log36 +log4 what does x=      Log On


   

Question 1053428: 2 log(x+6) = log36 +log4 what does x=
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+2%2Alog%28+x+%2B+6+%29+=+log%28+36+%29+%2B+log%28+4+%29+
+log%28+%28+x+%2B+6+%29%5E2+%29++=+log%28+36%2A4+%29+
+%28+x+%2B+6+%29%5E2+=+144+
+x%5E2+%2B+12x+%2B+36+=+144+
By observation:
+x%5E2+%2B+12x+%2B+6%5E2+=+12%5E2+
+%28+x+%2B+6+%29%5E2+=+12%5E2+
+x+%2B+6+=+12+
+x+=+6+
and, also, taking the negative square root of +12%5E2+,
+x+%2B+6+=+-12+
+x+=+-18+
This 2nd answer cannot be used because that would
result in +2%2Alog%28%28+-18+%2B+6+%29%29+=+2%2Alog%28%28+-12+%29%29+ and
you cannot get a negative result by raising a positive base
to either a + or a - log
So the answer is +x+=+6+