SOLUTION: log4(x+1)+ log4 (x-5)=2

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Question 688053: log4(x+1)+ log4 (x-5)=2
Found 2 solutions by lwsshak3, MathTherapy:
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
log4(x+1)+ log4 (x-5)=2
log4[(x+1)(x-5)]=log4(16)
(x+1)(x-5)=16
x^2-4x-5=16
x^2-4x-21=0
(x-7(x+3)=0
x=-3 (reject, (x+1)>0)
x=7

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!
log4(x+1)+ log4 (x-5)=2

log%284%2C+%28x+%2B+1%29%29+%2B+log%284%2C+%28x+-+5%29%29+=+2

x = - 3 (ignore as this will result in a negative log value)

highlight_green%28x+=+7%29

You can do the check!!

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