SOLUTION: solve log(x+2)+log x= 3 log 2 as algebraically and solve for any extraneous solutions.

Algebra ->  Exponential-and-logarithmic-functions -> SOLUTION: solve log(x+2)+log x= 3 log 2 as algebraically and solve for any extraneous solutions.      Log On


   

Question 391277: solve log(x+2)+log x= 3 log 2 as algebraically and solve for any extraneous solutions.
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!

log%28x%2B2%29%2Blog+x=+3+log+2
log%28x%28x%2B2%29%29=+log+2%5E3
x%28x%2B2%29+=+2%5E3
x%5E2%2B2x+=+8
x%5E2%2B2x-8+=+0
%28x%2B4%29%28x-2%29+=+0
x = {-4, 2}
Checking for extraneous solutions, we have to throw out the negative solution leaving:
x = 2