SOLUTION: log₂(x+20)- log₂(x+2)= log₂x

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Question 329043: log₂(x+20)- log₂(x+2)= log₂x
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
log%282%2C%28x%2B20%29%29-+log%282%2C%28x%2B2%29%29=+log%282%2C%28x%29%29
log%282%2C%28%28x%2B20%29%2F%28x%2B2%29%29%29=+log%282%2C%28x%29%29
%28x%2B20%29%2F%28x%2B2%29=+x
x%2B20=x%28x%2B2%29
x%2B20=x%5E2%2B2x
x%5E2%2Bx-20=0
%28x%2B5%29%28x-4%29=0
Only a positive solution is allowed since the log function requires a positive argument.
x-4=0
highlight%28x=4%29