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Pair of lines through (1, 1) and making...

Pair of lines through `(1, 1)` and making equal angle with `3x - 4y=1` and `12x +9y=1` intersect x-axis at `P_1` and `P_2` , then `P_1,P_2` may be

A

(a) `((8)/(7),0)` and `((9)/(7),0)`

B

(b) `((6)/(7),0)` and `(8,0)`

C

(c) `((8)/(7),0)` and `((1)/(8),0)`

D

(d) `(8,0)` and `((1)/(8),0)`

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To solve the problem of finding the points \( P_1 \) and \( P_2 \) where the pair of lines through the point \( (1, 1) \) intersects the x-axis, making equal angles with the lines \( 3x - 4y = 1 \) and \( 12x + 9y = 1 \), we can follow these steps: ### Step 1: Find the slopes of the given lines 1. **Convert the equations to slope-intercept form (y = mx + b)**: - For the line \( 3x - 4y = 1 \): \[ 4y = 3x - 1 \implies y = \frac{3}{4}x - \frac{1}{4} \] Thus, the slope \( m_1 = \frac{3}{4} \). - For the line \( 12x + 9y = 1 \): \[ 9y = -12x + 1 \implies y = -\frac{12}{9}x + \frac{1}{9} \implies y = -\frac{4}{3}x + \frac{1}{9} \] Thus, the slope \( m_2 = -\frac{4}{3} \). ### Step 2: Use the angle bisector property Since the lines make equal angles with the new lines, we can use the formula for the slopes of the angle bisectors: \[ \frac{m - m_1}{1 + m m_1} = \pm \frac{m - m_2}{1 + m m_2} \] ### Step 3: Set up the equations 1. **Using the positive case**: \[ \frac{m - \frac{3}{4}}{1 + m \cdot \frac{3}{4}} = \frac{m + \frac{4}{3}}{1 - m \cdot \frac{4}{3}} \] 2. **Cross-multiplying and simplifying**: - This leads to a quadratic equation in terms of \( m \). 3. **Using the negative case**: \[ \frac{m - \frac{3}{4}}{1 + m \cdot \frac{3}{4}} = -\frac{m + \frac{4}{3}}{1 - m \cdot \frac{4}{3}} \] 4. **Cross-multiplying and simplifying**: - This will also lead to a quadratic equation. ### Step 4: Solve for \( m \) After solving the equations from both cases, we will find two possible slopes \( m_1 \) and \( m_2 \). ### Step 5: Write the equations of the lines Using the point-slope form of the equation of a line \( y - y_1 = m(x - x_1) \): 1. For \( m_1 \): \[ y - 1 = m_1(x - 1) \] 2. For \( m_2 \): \[ y - 1 = m_2(x - 1) \] ### Step 6: Find the intersection points with the x-axis 1. Set \( y = 0 \) in both line equations to find \( P_1 \) and \( P_2 \): - For the first line, solve for \( x \) when \( y = 0 \). - For the second line, similarly solve for \( x \) when \( y = 0 \). ### Step 7: Identify the points \( P_1 \) and \( P_2 \) After solving, we will find the coordinates of \( P_1 \) and \( P_2 \). ### Final Answer The points \( P_1 \) and \( P_2 \) are: - \( P_1 = (8, 0) \) - \( P_2 = \left(\frac{6}{7}, 0\right) \)

To solve the problem of finding the points \( P_1 \) and \( P_2 \) where the pair of lines through the point \( (1, 1) \) intersects the x-axis, making equal angles with the lines \( 3x - 4y = 1 \) and \( 12x + 9y = 1 \), we can follow these steps: ### Step 1: Find the slopes of the given lines 1. **Convert the equations to slope-intercept form (y = mx + b)**: - For the line \( 3x - 4y = 1 \): \[ 4y = 3x - 1 \implies y = \frac{3}{4}x - \frac{1}{4} ...
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