Solving Logarithms Questions - Matt's Attempt

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Matt seeks validation for his solution to the logarithmic equation 5^(x-1) = 4^(1-3x). He derives the equation x = (log4 + log5) / (log5 + 3log4) and calculates the approximate value of x as 0.519. Feedback confirms that his steps appear correct, and he is advised to check his answer by substituting it back into the original equation. The discussion emphasizes the importance of verifying solutions in logarithmic problems. Overall, the approach and calculations are affirmed as accurate.
monkeyhead
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Just a quick check, I've spend hours trying to crack this. Have I gone the right way about it?

Homework Statement


Solve 5^(x-1)= 4^(1-3x)


Homework Equations





The Attempt at a Solution



(x-1)log5 = log4 (1-3x)

xlog5 - log5 = log4 - 3xlog4

xlog5 + 3xlog4= log4 + log 5

x(log5 + 3log4) = log4 + log 5

x= log4 + log 5/(log5 + 3log4)

= 0.519( 3dp)


Many thanks
Matt
 
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Looks correct, and I'm assuming that your actual operation was

x=\frac{\log 20}{\log{(5\times4^3)}}
 
I see thanks for the feedback
Matt
 
If you have a TI, just store your answer and then plug it back into your original equation and see if L=R.
 
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