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If point P(3,2) divides the line segment...

If point `P(3,2)` divides the line segment AB internally in the ratio of `3:2` and point `Q(-2,3)` divides AB externally in the ratio `4:3` then find the coordinates of points A and B.

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To find the coordinates of points A and B given the points P(3,2) and Q(-2,3) that divide the line segment AB in specific ratios, we can use the section formula. Let's break down the solution step by step. ### Step 1: Use the Section Formula for Internal Division Point P(3, 2) divides the line segment AB internally in the ratio 3:2. According to the section formula, if a point divides a line segment internally in the ratio m:n, the coordinates (x, y) of the point can be calculated as follows: \[ x = \frac{mx_2 + nx_1}{m+n} \] \[ y = \frac{my_2 + ny_1}{m+n} \] Here, let A be (x1, y1) and B be (x2, y2). For point P: - m = 3 - n = 2 - P(3, 2) = (x, y) Substituting the values, we get: \[ 3 = \frac{3x_2 + 2x_1}{3 + 2} \quad \text{(1)} \] \[ 2 = \frac{3y_2 + 2y_1}{3 + 2} \quad \text{(2)} \] ### Step 2: Simplify the Equations From equation (1): \[ 3(3 + 2) = 3x_2 + 2x_1 \] \[ 15 = 3x_2 + 2x_1 \quad \text{(Equation 1)} \] From equation (2): \[ 2(3 + 2) = 3y_2 + 2y_1 \] \[ 10 = 3y_2 + 2y_1 \quad \text{(Equation 2)} \] ### Step 3: Use the Section Formula for External Division Point Q(-2, 3) divides the line segment AB externally in the ratio 4:3. For external division, the formula is slightly different: \[ x = \frac{mx_2 - nx_1}{m-n} \] \[ y = \frac{my_2 - ny_1}{m-n} \] For point Q: - m = 4 - n = 3 - Q(-2, 3) = (x, y) Substituting the values, we get: \[ -2 = \frac{4x_2 - 3x_1}{4 - 3} \quad \text{(3)} \] \[ 3 = \frac{4y_2 - 3y_1}{4 - 3} \quad \text{(4)} \] ### Step 4: Simplify the External Division Equations From equation (3): \[ -2 = 4x_2 - 3x_1 \] \[ 4x_2 - 3x_1 = -2 \quad \text{(Equation 3)} \] From equation (4): \[ 3 = 4y_2 - 3y_1 \] \[ 4y_2 - 3y_1 = 3 \quad \text{(Equation 4)} \] ### Step 5: Solve the System of Equations Now we have four equations: 1. \(3x_2 + 2x_1 = 15\) (Equation 1) 2. \(3y_2 + 2y_1 = 10\) (Equation 2) 3. \(4x_2 - 3x_1 = -2\) (Equation 3) 4. \(4y_2 - 3y_1 = 3\) (Equation 4) #### Solving for x-coordinates: From Equation 1: \[ 2x_1 = 15 - 3x_2 \quad \Rightarrow \quad x_1 = \frac{15 - 3x_2}{2} \] Substituting \(x_1\) into Equation 3: \[ 4x_2 - 3\left(\frac{15 - 3x_2}{2}\right) = -2 \] Multiply through by 2 to eliminate the fraction: \[ 8x_2 - 3(15 - 3x_2) = -4 \] \[ 8x_2 - 45 + 9x_2 = -4 \] \[ 17x_2 = 41 \quad \Rightarrow \quad x_2 = \frac{41}{17} \] Now substitute \(x_2\) back to find \(x_1\): \[ x_1 = \frac{15 - 3\left(\frac{41}{17}\right)}{2} = \frac{15 - \frac{123}{17}}{2} = \frac{\frac{255 - 123}{17}}{2} = \frac{\frac{132}{17}}{2} = \frac{66}{17} \] #### Solving for y-coordinates: From Equation 2: \[ 2y_1 = 10 - 3y_2 \quad \Rightarrow \quad y_1 = \frac{10 - 3y_2}{2} \] Substituting \(y_1\) into Equation 4: \[ 4y_2 - 3\left(\frac{10 - 3y_2}{2}\right) = 3 \] Multiply through by 2: \[ 8y_2 - 3(10 - 3y_2) = 6 \] \[ 8y_2 - 30 + 9y_2 = 6 \] \[ 17y_2 = 36 \quad \Rightarrow \quad y_2 = \frac{36}{17} \] Now substitute \(y_2\) back to find \(y_1\): \[ y_1 = \frac{10 - 3\left(\frac{36}{17}\right)}{2} = \frac{10 - \frac{108}{17}}{2} = \frac{\frac{170 - 108}{17}}{2} = \frac{\frac{62}{17}}{2} = \frac{31}{17} \] ### Final Coordinates Thus, the coordinates of points A and B are: - A = \(\left(\frac{66}{17}, \frac{31}{17}\right)\) - B = \(\left(\frac{41}{17}, \frac{36}{17}\right)\)

To find the coordinates of points A and B given the points P(3,2) and Q(-2,3) that divide the line segment AB in specific ratios, we can use the section formula. Let's break down the solution step by step. ### Step 1: Use the Section Formula for Internal Division Point P(3, 2) divides the line segment AB internally in the ratio 3:2. According to the section formula, if a point divides a line segment internally in the ratio m:n, the coordinates (x, y) of the point can be calculated as follows: \[ x = \frac{mx_2 + nx_1}{m+n} \] ...
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Knowledge Check

  • If the line joining A(1,3,4) and B is divided by the point (-2,3,5) in the ratio 1:3 then the coordinates of B is

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    ` ( -11,3,8) `
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    C
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  • If point C(-4,1) divides the line segment joining the point A(2,-2) and B in the ratio 3:5 , then the coordinates of B are

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    (a) `(-14,6)`
    B
    (b) `(6,-14)`
    C
    (c) `(-14,-6)`
    D
    (d) `(-6,-14)`
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