SOLUTION: log(x^2-2x-31)/log(2)=2

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Question 370322: log(x^2-2x-31)/log(2)=2
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
log%28%28x%5E2-2x-31%29%29%2Flog%28%282%29%29=2
log%28%28x%5E2-2x-31%29%29=2%2Alog%28%282%29%29
log%28%28x%5E2-2x-31%29%29=log%28%282%5E2%29%29
x%5E2-2x-31=4
x%5E2-2x-35=0
%28x-7%29%28x%2B2%29=0
Two solutions:
x-7-0
x=7
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.
.
x%2B2=0
x=-2
However the negative value leads to a negative argument for the log function which is undefined.
.
.
.
highlight%28x=7%29