SOLUTION: please help me solve for x algebraically: log subscript 2 x + log subscript 2 (x+2) -log sub script 2 (4-x)=2

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Question 587178: please help me solve for x algebraically:
log subscript 2 x + log subscript 2 (x+2) -log sub script 2 (4-x)=2

Found 2 solutions by nerdybill, lwsshak3:
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
please help me solve for x algebraically:
log subscript 2 x + log subscript 2 (x+2) -log sub script 2 (4-x)=2
.
log%282%2Cx%29+%2B+log%282%2Cx%2B2%29+-+log%282%2C4-x%29+=+2
log%282%2Cx%28x%2B2%29%29+-+log%282%2C4-x%29+=+2
log%282%2Cx%28x%2B2%29%2F%284-x%29%29+=+2
x%28x%2B2%29%2F%284-x%29+=+2%5E2
x%28x%2B2%29%2F%284-x%29+=+4
x%28x%2B2%29+=+4%284-x%29
x%5E2%2B2x+=+16-4x
x%5E2%2B6x+=+16
x%5E2%2B6x-16+=+0
%28x%2B8%29%28x-2%29+=+0
x = {-8, 2}
We throw out the negative solution (extraneous) leaving:
x = 2

Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
please help me solve for x algebraically:
log subscript 2 x + log subscript 2 (x+2) -log sub script 2 (4-x)=2
**
log2(x)+log2(x+2)-log2(4-x)=2
place under single log
log2[x(x+2)/(4-x)]=2
convert to exponential form: base(2) raised to log of number(2)=number[x(x+2)/(4-x)]
2^2=[x(x+2)/(4-x)]=4
(x^2+2x)=16-4x
x^2+6x-16=0
(x+8)(x-2)=0
x=-8 (reject, x>0)
or
x=2