Question 715667: Solve the equation: log4 30-log4(x-1)-log4(x+2)=log4 3
Answer by lwsshak3(11628)   (Show Source):
You can put this solution on YOUR website! Solve the equation:
log4 (30)-log4(x-1)-log4(x+2)=log4 (3)
log4 (30)-(log4(x-1)+log4(x+2))=log4 (3)
log4 [(30/(x-1)(x-2)]=log(3)
(30/(x-1)(x-2)=3
30/3=(x-1)(x+2)
10=x^2+x-2
x^2+x-12=0
(x+4)(x-3)=0
x=-4 (reject, x≥0)
x=3
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