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If x and y are positive real numbers such that ` 2log(2y - 3x) = log x + log y," then find the value of " x/y`.

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To solve the equation \( 2 \log(2y - 3x) = \log x + \log y \), we will follow these steps: ### Step-by-Step Solution: 1. **Apply Logarithmic Properties**: We start with the equation: \[ 2 \log(2y - 3x) = \log x + \log y \] Using the property of logarithms that states \( a \log b = \log(b^a) \) and \( \log a + \log b = \log(ab) \), we can rewrite the equation as: \[ \log((2y - 3x)^2) = \log(xy) \] 2. **Remove the Logarithm**: Since the logarithmic function is one-to-one, we can eliminate the logarithm by exponentiating both sides: \[ (2y - 3x)^2 = xy \] 3. **Expand the Left Side**: Expanding the left side gives: \[ 4y^2 - 12xy + 9x^2 = xy \] 4. **Rearranging the Equation**: Rearranging the equation to one side results in: \[ 4y^2 - 12xy + 9x^2 - xy = 0 \] This simplifies to: \[ 4y^2 - 13xy + 9x^2 = 0 \] 5. **Substituting \( u = \frac{x}{y} \)**: Let \( u = \frac{x}{y} \), which implies \( x = uy \). Substituting this into the equation gives: \[ 4y^2 - 13(uy)y + 9(uy)^2 = 0 \] Simplifying, we have: \[ 4y^2 - 13uy^2 + 9u^2y^2 = 0 \] Factoring out \( y^2 \) (since \( y \neq 0 \)): \[ y^2(4 - 13u + 9u^2) = 0 \] Thus, we need to solve: \[ 9u^2 - 13u + 4 = 0 \] 6. **Using the Quadratic Formula**: The quadratic formula \( u = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \) applies here, where \( a = 9, b = -13, c = 4 \): \[ u = \frac{13 \pm \sqrt{(-13)^2 - 4 \cdot 9 \cdot 4}}{2 \cdot 9} \] Calculating the discriminant: \[ u = \frac{13 \pm \sqrt{169 - 144}}{18} = \frac{13 \pm \sqrt{25}}{18} = \frac{13 \pm 5}{18} \] This gives us two potential solutions: \[ u = \frac{18}{18} = 1 \quad \text{and} \quad u = \frac{8}{18} = \frac{4}{9} \] 7. **Evaluating the Solutions**: Since \( u = \frac{x}{y} \), we have two potential values: \( u = 1 \) and \( u = \frac{4}{9} \). However, if \( u = 1 \), then \( x = y \) which leads to \( 2y - 3y = -y \), and the logarithm of a negative number is undefined. Therefore, we discard \( u = 1 \). 8. **Final Result**: The only valid solution is: \[ \frac{x}{y} = \frac{4}{9} \]

To solve the equation \( 2 \log(2y - 3x) = \log x + \log y \), we will follow these steps: ### Step-by-Step Solution: 1. **Apply Logarithmic Properties**: We start with the equation: \[ 2 \log(2y - 3x) = \log x + \log y ...
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