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Solve the equation. log5x=log3+log(x−4)

User Justin Lam
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Final answer:

The given logarithmic equation is solved by using properties of logarithms to combine terms and solve for x. However, the calculated solution x = -6 is not valid for a logarithmic function since the argument cannot be negative, therefore the equation has no real solutions.

Step-by-step explanation:

To solve the equation log(5x) = log(3) + log(x - 4), we can use the properties of logarithms. The property that log(a) + log(b) = log(ab) allows us to combine the right side of the equation:

log(3) + log(x - 4) = log(3(x - 4))

Now we have:

log(5x) = log(3(x - 4))

Since the logarithms are equal, the arguments must be equal as well:

5x = 3(x - 4)

Expanding and solving for x:

5x = 3x - 12

2x = -12

x = -6

However, since x cannot be negative in log(x - 4) because the logarithm of a negative number is undefined, this solution is not valid within the real number system. Thus, there is no solution to the equation in real numbers.

User Gil Grencho
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