Question 748318: log(x-3) + log(x+2) = log(4x)
I need to know what steps to take to get the answer. Thank you!
Answer by nerdybill(7384)   (Show Source):
You can put this solution on YOUR website! log(x-3) + log(x+2) = log(4x)
adding two logs is equivalent to multiplication:
log(x-3)(x+2) = log(4x)
now, we can eliminate the logs from both sides:
(x-3)(x+2) = (4x)
x^2-x-6 = 4x
x^2-5x-6 = 0
(x+1)(x-6) = 0
x = {-1, 6}
we throw out the -1 (extraneous solution) leaving
x = 6
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