SOLUTION: log base 2 (x+3)+ log base 2 (x-1)=5 (solve, list answers as integers or simplified fractions) x=?

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Question 443702: log base 2 (x+3)+ log base 2 (x-1)=5 (solve, list answers as integers or simplified fractions)
x=?
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
log base 2 (x+3)+ log base 2 (x-1)=5
log base 2 (x+3)(x-1)=5
(x+3)(x-1)=2^5
x^2+2x-3 =32
x^2+2x-35 = 0
(x+7)(x-5) = 0
x = {-7,5}
The negative answer is "extraneous" -- toss it out leaving:
x = 5