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If the slope of one of the lines represe...

If the slope of one of the lines represented by `ax^(2)+(3a+1)xy+3y^(2)=0` be reciprocal of the slope of the other, then the slope of the lines are

A

`3/2,2/3`

B

`1/2,2/1`

C

`1/3,3`

D

`(-1)/3,-3`

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To solve the problem, we need to find the slopes of the lines represented by the equation \( ax^2 + (3a + 1)xy + 3y^2 = 0 \) under the condition that the slopes are reciprocals of each other. ### Step-by-Step Solution 1. **Identify the coefficients**: The given equation is \( ax^2 + (3a + 1)xy + 3y^2 = 0 \). Here, we can identify: - \( a' = a \) - \( 2h' = 3a + 1 \) (coefficient of \( xy \)) - \( b' = 3 \) 2. **Use the formulas for slopes**: For a pair of straight lines represented by the general equation \( a'x^2 + 2h'xy + b'y^2 = 0 \): - The sum of the slopes \( m_1 + m_2 = -\frac{2h'}{b'} \) - The product of the slopes \( m_1 m_2 = \frac{a'}{b'} \) 3. **Calculate \( m_1 + m_2 \)**: \[ m_1 + m_2 = -\frac{2(3a + 1)}{3} = -\frac{6a + 2}{3} \] 4. **Calculate \( m_1 m_2 \)**: \[ m_1 m_2 = \frac{a}{3} \] 5. **Set up the relationship between slopes**: Given that the slopes are reciprocals, we have: \[ m_2 = \frac{1}{m_1} \implies m_1 m_2 = 1 \] Therefore, we can set: \[ m_1 m_2 = 1 = \frac{a}{3} \] This gives us: \[ a = 3 \] 6. **Substitute \( a \) back into the sum of slopes**: Now substituting \( a = 3 \) into the equation for \( m_1 + m_2 \): \[ m_1 + m_2 = -\frac{6(3) + 2}{3} = -\frac{18 + 2}{3} = -\frac{20}{3} \] 7. **Set up the quadratic equation**: We now have: \[ m_1 + m_2 = -\frac{20}{3} \quad \text{and} \quad m_1 m_2 = 1 \] This leads to the quadratic equation: \[ x^2 + \frac{20}{3}x + 1 = 0 \] 8. **Multiply through by 3 to eliminate the fraction**: \[ 3x^2 + 20x + 3 = 0 \] 9. **Use the quadratic formula to find the slopes**: The roots of the equation can be found using the quadratic formula: \[ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} = \frac{-20 \pm \sqrt{20^2 - 4 \cdot 3 \cdot 3}}{2 \cdot 3} \] \[ = \frac{-20 \pm \sqrt{400 - 36}}{6} = \frac{-20 \pm \sqrt{364}}{6} = \frac{-20 \pm 2\sqrt{91}}{6} = \frac{-10 \pm \sqrt{91}}{3} \] 10. **Final slopes**: Thus, the slopes of the lines are: \[ m_1 = \frac{-10 + \sqrt{91}}{3}, \quad m_2 = \frac{-10 - \sqrt{91}}{3} \]

To solve the problem, we need to find the slopes of the lines represented by the equation \( ax^2 + (3a + 1)xy + 3y^2 = 0 \) under the condition that the slopes are reciprocals of each other. ### Step-by-Step Solution 1. **Identify the coefficients**: The given equation is \( ax^2 + (3a + 1)xy + 3y^2 = 0 \). Here, we can identify: - \( a' = a \) - \( 2h' = 3a + 1 \) (coefficient of \( xy \)) ...
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