SOLUTION: Solve the following logarithmic equation. log(base5)(x+15)+log(base5)(x+134)=4

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Question 646070: Solve the following logarithmic equation. log(base5)(x+15)+log(base5)(x+134)=4
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
Solve the following logarithmic equation.
log(base5)(x+15)+log(base5)(x+134)=4
place under single log
log5[(x+15)(x+134)]=4
convert to exponential form
5^4=(x+15)(x+134)
625=x^2+149x+2010
x^2+149x+1385=0
solve for x by following quadratic formula:
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
a=1, b=149, c=1385
ans:
x≈-139.039 (reject,(x+15)>0)
or
x≈-9.961