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Solve the following pair of equations: ...

Solve the following pair of equations:
`(2xy)/(x+ y)= (3)/(2), (xy)/(2x- y)= (-3)/(10), x+y ne 0, 2x-y ne 0`

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To solve the given pair of equations: 1. **Equations**: - \( \frac{2xy}{x + y} = \frac{3}{2} \) (Equation 1) - \( \frac{xy}{2x - y} = -\frac{3}{10} \) (Equation 2) ### Step 1: Simplify Equation 1 Start with the first equation: \[ \frac{2xy}{x + y} = \frac{3}{2} \] Cross-multiply to eliminate the fraction: \[ 2xy \cdot 2 = 3(x + y) \] This simplifies to: \[ 4xy = 3x + 3y \] Rearranging gives: \[ 4xy - 3x - 3y = 0 \quad \text{(Equation 1')} \] ### Step 2: Simplify Equation 2 Now simplify the second equation: \[ \frac{xy}{2x - y} = -\frac{3}{10} \] Cross-multiply: \[ xy \cdot 10 = -3(2x - y) \] This simplifies to: \[ 10xy = -6x + 3y \] Rearranging gives: \[ 10xy + 6x - 3y = 0 \quad \text{(Equation 2')} \] ### Step 3: Substitute Variables Let \( u = \frac{1}{x} \) and \( v = \frac{1}{y} \). Then: - From Equation 1': \[ 4 \left(\frac{1}{u}\right)\left(\frac{1}{v}\right) - 3\left(\frac{1}{u}\right) - 3\left(\frac{1}{v}\right) = 0 \] Multiplying through by \( uv \): \[ 4 - 3v - 3u = 0 \implies 3u + 3v = 4 \implies u + v = \frac{4}{3} \quad \text{(Equation 3)} \] - From Equation 2': \[ 10 \left(\frac{1}{u}\right)\left(\frac{1}{v}\right) + 6\left(\frac{1}{u}\right) - 3\left(\frac{1}{v}\right) = 0 \] Multiplying through by \( uv \): \[ 10 + 6v - 3u = 0 \implies 3u - 6v = 10 \quad \text{(Equation 4)} \] ### Step 4: Solve the System of Equations Now we have a system of equations: 1. \( u + v = \frac{4}{3} \) (Equation 3) 2. \( 3u - 6v = 10 \) (Equation 4) From Equation 3, express \( u \): \[ u = \frac{4}{3} - v \] Substituting \( u \) into Equation 4: \[ 3\left(\frac{4}{3} - v\right) - 6v = 10 \] This simplifies to: \[ 4 - 3v - 6v = 10 \implies -9v = 6 \implies v = -\frac{2}{3} \] Substituting \( v \) back into Equation 3: \[ u - \frac{2}{3} = \frac{4}{3} \implies u = 2 \] ### Step 5: Find Values of x and y Recall: - \( u = \frac{1}{x} \) implies \( x = \frac{1}{u} = \frac{1}{2} \) - \( v = \frac{1}{y} \) implies \( y = \frac{1}{v} = -\frac{3}{2} \) ### Final Solution Thus, the solution to the system of equations is: \[ x = \frac{1}{2}, \quad y = -\frac{3}{2} \]
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