SOLUTION: ln(x)+ln(x+4)=ln(5)

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Question 139105This question is from textbook Algebra 2
: ln(x)+ln(x+4)=ln(5) This question is from textbook Algebra 2

Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
adding logs is multiplying quantities

x(x+4)=5 __ x^2+4x-5=0

factoring __ (x+5)(x-1)=0

x+5=0 __ x=-5 __ logs are not defined for negative quantities

x-1=0 __ x=1