SOLUTION: Log2 x+log2(x-3)=2

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Question 333513: Log2 x+log2(x-3)=2
Answer by benazir.sj@gmail.com(109) About Me  (Show Source):
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Log2 x+log2(x-3)=2
property of log
log a + log b = log a*b
and 2 is the base
log2[x*(x-3)]=2
log[x*(x-3)=2^2
x(x-3)=4
x^2 -3x =4
x^2-3x-4=0
x^2-4x+x-4=0
x(x-4)+1(x-4)=0
(x+1)(x-4)=0
x=-1 or x=4
x= -1,4