COMEDK2023Morning ShiftMathematicsThree Dimensional GeometryActual
The place x-2 y+z=0 is parallel to the line
Options
- Ax-3 4 = y-4 5 = z-3 6
- Bx-2 1 = y-2 -2 = z-3 1
- Cx-4 3 = y-5 4 = z-6 3
- Dx-2 2 = y-3 3 = z-4 4
Correct answer
A. x-3 4 = y-4 5 = z-3 6
Step-by-step solution
A line with direction vector b = a i + b j + c k is parallel to a plane with normal vector n = A i + B j + C k if and only if n b = 0 . The normal vector to the plane x - 2y + z = 0 is n = 1 i - 2 j + 1 k . We check the dot product for each option: For (RUsrb), b = 4 i + 5 j + 6 k . n b = (1)(4) + (-2)(5) + (1)(6) = 4 - 10 + 6 = 0 . Since the dot product is zero, the line is parallel to the plane. We also check if the line lies in the plane by testing a point on the line, such as (3, 4, 3) . Substituting into the p