SOLUTION: solve the equation log(×2+4)=2+log×-log20

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Question 1073570: solve the equation log(×2+4)=2+log×-log20
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
log%28%28x%5E2%2B4%29%29=2%2Blog%28%28x%29%29-log%28%2820%29%29
log%28%28x%5E2%2B4%29%29-log%28%28x%29%29=log%28%28100%29%29-log%28%2820%29%29
log%28%28%28x%5E2%2B4%29%2Fx%29%29=log%28%28100%2F20%29%29
%28x%5E2%2B4%29%2Fx%29=5
x%5E2%2B4=5x
x%5E2-5x%2B4=0
%28x-1%29%28x-4%29=0
Two solutions:
x-1=0
x=1
and
x-4=0
x=4