You can put this solution on YOUR website! log2 (5x+7) - log2 x = 2
log2(a) - log2(b) = log2 (a/b)
using the above identity
log2 ((5x+7)/x) = 2
log 2 to the base 2 is 1 i.e log2 2 = 1
2 can be written as 2*1 = 2log2 (2) = log2 (4)
log2 ((5x+7)/x) = log2 (4)
since the log on the right and the left side is with the same base
(5x + 7)/x = 4
5x + 7 = 4*x
x = -7
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