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What is the solution to 2 log Subscript 9 Baseline (x) = log Subscript 9 Baseline 8 + log Subscript 9 Baseline (x minus 2) x = negative 4 x = negative 2 x = 4 x = 8

User JRomio
by
4.2k points

2 Answers

7 votes

Answer:

x=4

Explanation:

User Osi
by
4.4k points
5 votes

Answer:


\large\boxed{\large\boxed{x=4}}

Explanation:

The equation to solve is:


2\log_9 x=\log_9 8+\log_9 (x-2)

1. On the left-hand side use: "The product of a constant by a logarithm is equal to the logarithm raised to the constant"

Thus, the left-hand side is:


2\log_9 x=\log_9 x^2

2. On the right-hand side use "The sum of two logarithms with the same base is the logarithm of the product":

Then, on the right-hand side:


\log_9 8+\log_9 (x-2)=\log_9 8(x-2)

3. Make them equal:


\log_9 x^2=\log_9 8(x-2)

4. Since the two functions are the same, make the arguments equal:


x^2=8(x-2)

5. Solve the equation:


x^2=8x-16\\\\x^2-8x+16=0\\\\(x-4)^2=0\\\\x-4=0\\\\x=4\leftarrow solution

User Alex Sax
by
4.2k points