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Solve for x and y : (y+7)/(5)=(2y-x)/(...

Solve for x and y :
`(y+7)/(5)=(2y-x)/(4)+3x-5`
`(7-5x)/(2)+(3-4y)/(6)=5y-18`

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The correct Answer is:
To solve the given simultaneous linear equations for \(x\) and \(y\): 1. **Write down the equations:** \[ \frac{y + 7}{5} = \frac{2y - x}{4} + 3x - 5 \quad \text{(Equation 1)} \] \[ \frac{7 - 5x}{2} + \frac{3 - 4y}{6} = 5y - 18 \quad \text{(Equation 2)} \] 2. **Clear the fractions in Equation 1:** Multiply through by 20 (the least common multiple of the denominators 5 and 4): \[ 20 \cdot \frac{y + 7}{5} = 20 \cdot \left( \frac{2y - x}{4} + 3x - 5 \right) \] This simplifies to: \[ 4(y + 7) = 5(2y - x) + 60x - 100 \] Expanding both sides: \[ 4y + 28 = 10y - 5x + 60x - 100 \] Combine like terms: \[ 4y + 28 = 10y + 55x - 100 \] Rearranging gives: \[ 55x + 6y = 128 \quad \text{(Equation 1 simplified)} \] 3. **Clear the fractions in Equation 2:** Multiply through by 6 (the least common multiple of the denominators 2 and 6): \[ 6 \cdot \left( \frac{7 - 5x}{2} + \frac{3 - 4y}{6} \right) = 6(5y - 18) \] This simplifies to: \[ 3(7 - 5x) + (3 - 4y) = 30y - 108 \] Expanding both sides: \[ 21 - 15x + 3 - 4y = 30y - 108 \] Combine like terms: \[ 24 - 15x - 4y = 30y - 108 \] Rearranging gives: \[ 15x + 34y = 132 \quad \text{(Equation 2 simplified)} \] 4. **Now we have a system of equations:** \[ 55x + 6y = 128 \quad \text{(1)} \] \[ 15x + 34y = 132 \quad \text{(2)} \] 5. **Solve for \(y\) in terms of \(x\) from Equation (1):** \[ 6y = 128 - 55x \] \[ y = \frac{128 - 55x}{6} \] 6. **Substitute \(y\) into Equation (2):** \[ 15x + 34\left(\frac{128 - 55x}{6}\right) = 132 \] Multiply through by 6 to eliminate the fraction: \[ 90x + 34(128 - 55x) = 792 \] Expanding gives: \[ 90x + 4352 - 1870x = 792 \] Combine like terms: \[ -1780x + 4352 = 792 \] Rearranging gives: \[ -1780x = 792 - 4352 \] \[ -1780x = -3560 \] Dividing by -1780: \[ x = 2 \] 7. **Substitute \(x\) back into the equation for \(y\):** \[ y = \frac{128 - 55(2)}{6} \] \[ y = \frac{128 - 110}{6} \] \[ y = \frac{18}{6} = 3 \] 8. **Final solution:** \[ x = 2, \quad y = 3 \]
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