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Solve the equation. log₅(x+12)+log₅(x-12)=2 What is the equivalent equation that must be s

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Final answer:

To solve the equation log₅(x+12) + log₅(x-12) = 2, combine the log terms into log₅((x+12)(x-12)) = 2 using the product rule for logarithms, then convert to exponential form and solve for x, resulting in x = 13 after checking for extraneous solutions.

Step-by-step explanation:

To solve the equation log₅(x+12) + log₅(x-12) = 2, we must first use the properties of logarithms to combine the two log terms. According to the product rule for logarithms, which states that logₙ(a) + logₙ(b) = logₙ(ab), we can combine them into a single logarithm:

log₅((x+12)(x-12)) = 2

This simplifies to:

log₅(x² - 144) = 2

Now, to remove the logarithm, we rewrite the equation in exponential form:

5² = x² - 144

This gives us:

25 = x² - 144

Now, add 144 to both sides to isolate the x² term:

x² = 169

Finally, take the square root of both sides, remembering to consider both the positive and negative roots:

x = ±√169

x = ± 13

However, since the original equation contains log terms, we must check for extraneous solutions. We can only take the logarithm of positive numbers, so x must be greater than 12 to be a valid solution since x-12 must be positive. Thus, the only solution is x = 13.

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