SOLUTION: Please help me to solve this equation: log x + log(3x+5)=1

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Question 747856: Please help me to solve this equation: log x + log(3x+5)=1
Found 2 solutions by Kg2003, MathLover1:
Answer by Kg2003(10) About Me  (Show Source):
You can put this solution on YOUR website!
Use log properties.
+log%28%28x%29%283x%2B5%29%29=1+
+log%283x%5E2%2B5x%29=1+
Next change to exponential form. (It's base 10)
+10%5E1=3x%5E2%2B5x+
+3x%5E2%2B5x-10=0+
Next use quadradic formula to factor. The negative answer won't work because you can't take the log of a negative number. Your answer is approximately 1.1736

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

log+%28x%29+%2B+log%283x%2B5%29=1...it is base 10 log
%28log+%28x%29+%2B+log%283x%2B5%29%29%2Flog%2810%29=1
log+%28x%283x%2B5%29%29=1%2Alog%2810%29
log+%28x%283x%2B5%29%29=log%2810%29
x%283x%2B5%29=10
3x%5E2%2B5x=10
3x%5E2%2B5x-10=0....use quadratic formula

x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+

x+=+%28-5+%2B-+sqrt%28+5%5E2-4%2A3%2A%28-10%29+%29%29%2F%282%2A3%29+

x+=+%28-5+%2B-+sqrt%28+25%2B120+%29%29%2F6+

x+=+%28-5+%2B-+sqrt%28+145+%29%29%2F6+

x+=+%28-5+%2B-+12.042%29%2F6+
solutions:
x+=+%28-5+%2B12.042%29%2F6+
x+=+7.042%2F6+
highlight%28x+=+1.174%29+
since logarithm of negative number unidentified, we will use only
positive solution highlight%28x+=+1.174%29+