Question 525231: Solve for x:
2 log base 5(7-x)-log base 5 3=log base 5 12
Answer by lwsshak3(11628)   (Show Source):
You can put this solution on YOUR website! Solve for x:
2 log base 5(7-x)-log base 5 3=log base 5 12
log5(7-x)^2-log5(3)-log5(12)=0
log5(7-x)^2-[(log5(3)+log5(12)]=0
place under single log
log5[(7-x)^2/3*12]=0
log5[(7-x)^2/36]=0
convert to exponential form: base(5) raised to log of number(0)=number(7-x)^2/36)
5^0=(7-x)^2/36=1
(7-x)^2=36
take sqrt of both sides
7-x=±√36=±6
x=7±6
x=1
or
x=13(reject,(7-x)>0
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