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Find the ratio in which the plane 2x-3y+...

Find the ratio in which the plane 2x-3y+z=8 divides the line segment joining the points A(3, -2,1) and B(1, 4, -3). Also find the point of intersection of the line and the plane.

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To solve the problem, we need to find the ratio in which the plane \(2x - 3y + z = 8\) divides the line segment joining the points \(A(3, -2, 1)\) and \(B(1, 4, -3)\). We will also find the point of intersection of the line and the plane. ### Step 1: Determine the coordinates of the point dividing the line segment in the ratio \(m:n\) Let the point of intersection be \(P(\alpha, \beta, \gamma)\). According to the section formula, if a point divides the line segment joining points \(A(x_1, y_1, z_1)\) and \(B(x_2, y_2, z_2)\) in the ratio \(m:n\), then the coordinates of point \(P\) can be expressed as: \[ \alpha = \frac{mx_2 + nx_1}{m+n}, \quad \beta = \frac{my_2 + ny_1}{m+n}, \quad \gamma = \frac{mz_2 + nz_1}{m+n} \] For our case, \(A(3, -2, 1)\) and \(B(1, 4, -3)\). Let the ratio in which the plane divides the line segment be \(m:1\) (where \(n = 1\)). Thus, we have: \[ \alpha = \frac{m \cdot 1 + 1 \cdot 3}{m + 1}, \quad \beta = \frac{m \cdot 4 + 1 \cdot (-2)}{m + 1}, \quad \gamma = \frac{m \cdot (-3) + 1 \cdot 1}{m + 1} \] ### Step 2: Substitute the coordinates into the plane equation The coordinates \((\alpha, \beta, \gamma)\) must satisfy the equation of the plane \(2x - 3y + z = 8\). Therefore, we substitute \(\alpha\), \(\beta\), and \(\gamma\) into the plane equation: \[ 2\left(\frac{m \cdot 1 + 3}{m + 1}\right) - 3\left(\frac{4m - 2}{m + 1}\right) + \left(\frac{-3m + 1}{m + 1}\right) = 8 \] ### Step 3: Simplify the equation Now, we simplify the left-hand side: \[ \frac{2(m + 3) - 3(4m - 2) - 3m + 1}{m + 1} = 8 \] This simplifies to: \[ \frac{2m + 6 - 12m + 6 - 3m + 1}{m + 1} = 8 \] Combining like terms gives: \[ \frac{-13m + 13}{m + 1} = 8 \] ### Step 4: Cross-multiply and solve for \(m\) Cross-multiplying gives: \[ -13m + 13 = 8(m + 1) \] Expanding the right side: \[ -13m + 13 = 8m + 8 \] Rearranging terms: \[ 13 - 8 = 8m + 13m \] \[ 5 = 21m \] Thus, we find: \[ m = \frac{5}{21} \] ### Step 5: Determine the ratio The ratio in which the plane divides the line segment \(AB\) is \(m:1 = \frac{5}{21}:1\). Therefore, the ratio is: \[ 5:21 \] ### Step 6: Find the coordinates of the point of intersection Now, we substitute \(m = \frac{5}{21}\) back into the expressions for \(\alpha\), \(\beta\), and \(\gamma\): \[ \alpha = \frac{\frac{5}{21} \cdot 1 + 3}{\frac{5}{21} + 1} = \frac{\frac{5}{21} + \frac{63}{21}}{\frac{5}{21} + \frac{21}{21}} = \frac{\frac{68}{21}}{\frac{26}{21}} = \frac{68}{26} = \frac{34}{13} \] \[ \beta = \frac{\frac{5}{21} \cdot 4 - 2}{\frac{5}{21} + 1} = \frac{\frac{20}{21} - \frac{42}{21}}{\frac{26}{21}} = \frac{-\frac{22}{21}}{\frac{26}{21}} = -\frac{22}{26} = -\frac{11}{13} \] \[ \gamma = \frac{\frac{5}{21} \cdot (-3) + 1}{\frac{5}{21} + 1} = \frac{-\frac{15}{21} + \frac{21}{21}}{\frac{26}{21}} = \frac{\frac{6}{21}}{\frac{26}{21}} = \frac{6}{26} = \frac{3}{13} \] ### Final Result Thus, the coordinates of the point of intersection are: \[ P\left(\frac{34}{13}, -\frac{11}{13}, \frac{3}{13}\right) \] ### Summary of Results 1. The ratio in which the plane divides the line segment \(AB\) is \(5:21\). 2. The point of intersection of the line and the plane is \(P\left(\frac{34}{13}, -\frac{11}{13}, \frac{3}{13}\right)\).

To solve the problem, we need to find the ratio in which the plane \(2x - 3y + z = 8\) divides the line segment joining the points \(A(3, -2, 1)\) and \(B(1, 4, -3)\). We will also find the point of intersection of the line and the plane. ### Step 1: Determine the coordinates of the point dividing the line segment in the ratio \(m:n\) Let the point of intersection be \(P(\alpha, \beta, \gamma)\). According to the section formula, if a point divides the line segment joining points \(A(x_1, y_1, z_1)\) and \(B(x_2, y_2, z_2)\) in the ratio \(m:n\), then the coordinates of point \(P\) can be expressed as: \[ \alpha = \frac{mx_2 + nx_1}{m+n}, \quad \beta = \frac{my_2 + ny_1}{m+n}, \quad \gamma = \frac{mz_2 + nz_1}{m+n} ...
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