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Find the equation of the plane passing t...

Find the equation of the plane passing through the intersection of the planes `2x+2y-3z-7=0 and 2x+5y+3z-9=0` such that the intercepts made by the resulting plane one the x-axis and the z-axis are equal.

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To find the equation of the plane passing through the intersection of the planes \(2x + 2y - 3z - 7 = 0\) and \(2x + 5y + 3z - 9 = 0\) such that the intercepts made by the resulting plane on the x-axis and the z-axis are equal, we can follow these steps: ### Step 1: Write the equations of the given planes The equations of the two planes are: 1. \(P_1: 2x + 2y - 3z - 7 = 0\) 2. \(P_2: 2x + 5y + 3z - 9 = 0\) ### Step 2: Form the equation of the resulting plane The equation of any plane passing through the intersection of these two planes can be expressed as: \[ P = P_1 + \lambda P_2 \] Substituting \(P_1\) and \(P_2\): \[ P = (2x + 2y - 3z - 7) + \lambda(2x + 5y + 3z - 9) \] This simplifies to: \[ P = (2 + 2\lambda)x + (2 + 5\lambda)y + (-3 + 3\lambda)z - (7 + 9\lambda) = 0 \] ### Step 3: Identify the coefficients From the equation, we can identify the coefficients: - Coefficient of \(x\): \(A = 2 + 2\lambda\) - Coefficient of \(y\): \(B = 2 + 5\lambda\) - Coefficient of \(z\): \(C = -3 + 3\lambda\) - Constant term: \(D = -(7 + 9\lambda)\) ### Step 4: Find the intercepts The intercepts on the axes can be found using the formula: - Intercept on the x-axis: \(x = -\frac{D}{A} = \frac{7 + 9\lambda}{2 + 2\lambda}\) - Intercept on the z-axis: \(z = -\frac{D}{C} = \frac{7 + 9\lambda}{-3 + 3\lambda}\) ### Step 5: Set the intercepts equal According to the problem, the intercepts on the x-axis and z-axis are equal: \[ \frac{7 + 9\lambda}{2 + 2\lambda} = \frac{7 + 9\lambda}{-3 + 3\lambda} \] Cross-multiplying gives: \[ (7 + 9\lambda)(-3 + 3\lambda) = (7 + 9\lambda)(2 + 2\lambda) \] ### Step 6: Solve for \(\lambda\) Assuming \(7 + 9\lambda \neq 0\), we can divide both sides by \(7 + 9\lambda\): \[ -3 + 3\lambda = 2 + 2\lambda \] Rearranging gives: \[ 3\lambda - 2\lambda = 2 + 3 \] \[ \lambda = 5 \] ### Step 7: Substitute \(\lambda\) back into the plane equation Substituting \(\lambda = 5\) back into the equation of the plane: \[ P = (2 + 2(5))x + (2 + 5(5))y + (-3 + 3(5))z - (7 + 9(5)) = 0 \] This simplifies to: \[ 12x + 27y + 12z - 50 = 0 \] ### Final Equation Rearranging gives the final equation of the plane: \[ 12x + 27y + 12z = 50 \]
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