NTA Abhyas JEE Main2020MathematicsThree Dimensional GeometryPractice
Let A be the point 1 , 2 , 3 and B be a point on the line x - 1 - 2 = y + 1 3 = z - 5 4 = k . The value of k such that line A B is perpendicular to the plane 4x + 9 y - 18 z = 6 is
Options
- A- 2 5
- B1 5
- C2 5
- Dno such value of k is possible
Correct answer
C. 2 5
Step-by-step solution
Coordinates of the point B are 2 k + 1 , 3 k − 1 , 4 k + 5 A vector parallel to A B is − 2 k i ^ + 3 k − 3 j ^ + 4 k + 2 k ^ ∵ the line A B is perpendicular to the given plane Hence, - 2 k 4 = 3 k - 3 9 = 4 k + 2 - 18 - 18 k = 12 k - 1 2 k = 2 5