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If log₂(4x + 6) = 4, then x = ____
You may enter the exact value or round to 4 decimal places.

If log₂(4x + 6) = 4, then x = ____ You may enter the exact value or round to 4 decimal-example-1
User CP Sean
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1 Answer

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Answer: -1/2

Step-by-step explanation: To solve this problem, we can use the properties of logarithms to isolate the variable x on one side of the equation. The properties of logarithms tell us that the logarithm of a product is the sum of the logarithms of the factors, and that the logarithm of a power is the exponent times the logarithm of the base.

If log₂(4x + 6) = 4, we can rewrite the left side of the equation as follows: log₂(4x + 6) = log₂(2^4 * (2x + 3))

Then, using the property of logarithms that the logarithm of a product is the sum of the logarithms of the factors, we can simplify the equation as follows: log₂(4x + 6) = 4 + log₂(2x + 3)

Now, we can use the property of logarithms that the logarithm of a power is the exponent times the logarithm of the base to simplify the equation even further: log₂(4x + 6) = 4 + 1 * log₂(2x + 3)

Since the logarithm of a power is the exponent times the logarithm of the base, this means that the logarithm of a number is the logarithm of that number divided by the logarithm of the base. Therefore, we can divide both sides of the equation by log₂ to isolate the variable x on one side of the equation:

log₂(4x + 6) / log₂ = 4 + 1 * log₂(2x + 3) / log₂

(4x + 6) / 1 = 4 + (2x + 3) / 1

4x + 6 = 4 + 2x + 3

4x + 6 = 2x + 7

2x = -1

x = -1/2

Therefore, if log₂(4x + 6) = 4, then x = -1/2.

User Sajeev C
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