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Question
Select the correct answer from given alternatives.
If log (5x – 9) – log (x + 3) = log 2 then x = ...............
Options
3
5
2
7
Solution
If log (5x – 9) – log (x + 3) = log 2 then x = 5
Explanation:
log (5x – 9) – log (x + 3) = log 2
`therefore (5x - 9)/(x + 3) = 2`
`therefore 3x = 9 + 6`
∴ x = 5
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