SOLUTION: What is the value of X in this equation? log{{{7}}}X + log{{{7}}}X - log{{{7}}}3 = log{{{7}}}12
I was thinking that you could add log{{{7}}}3 to both sides of the equation. Howeve
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-> SOLUTION: What is the value of X in this equation? log{{{7}}}X + log{{{7}}}X - log{{{7}}}3 = log{{{7}}}12
I was thinking that you could add log{{{7}}}3 to both sides of the equation. Howeve
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Question 20546: What is the value of X in this equation? logX + logX - log3 = log12
I was thinking that you could add log3 to both sides of the equation. However I don't know what to do next. Can you please help me out? Answer by AnlytcPhil(1810) (Show Source):
You can put this solution on YOUR website! log7X + log7X = log712 + log73
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The two terms on the left are just alike so when you add them you just get 2 of
them! That is, log7x + log7x = 2·log7x. So now you have
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2·log7X = log712 + log73
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Use the rule N·logBU = logBUN on the left
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log7X2 = log712 + log73
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Now use the rule logBU + logBV = logBUV
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log7X2 = log7(12·3)
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Now raise both sides to the 7 power, which is the same as dropping the logs.
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X2 = 36
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X = ±6, but we cannot take logs of negative numbers, so the answer is X = 6
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Edwin
AnlytcPhil@aol.com
