SOLUTION: log(9x+5)-log(x^(2)-1)=1/2

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Question 663329: log(9x+5)-log(x^(2)-1)=1/2
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
log(9x+5)-log(x^(2)-1)=1/2
place under single log
log[(9x+5)/(x^2-1)]=1/2
convert to exponential form:
10^(1/2)=(9x+5)/(x^2-1)=√10
√10(x^2-1)=9x+5
√10x^2-√10=9x+5
√10x^2-9x-√10-5=0
3.16x^2-9x-8.16=0
solve by following quadratic formula:
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
a=3.16, b=-9, c=-8.16
ans:
x≈-0.723(reject, (9x+5)>0)
or
x≈3.571