The distance of the point from the plane measured parallel to the line is
- A.
- B.
- C.
- D.
Show answer and solution
Correct option: C
Solution
The line through (-1, 9, -16) parallel to the given direction (3, -4, 12) is parametrized as:
x = -1 + 3t, y = 9 - 4t, z = -16 + 12t.
Substitute into 2x + 3y - z = 5:
2(-1 + 3t) + 3(9 - 4t) - (-16 + 12t) = 5
-2 + 6t + 27 - 12t + 16 - 12t = 5
41 - 18t = 5
18t = 36, so t = 2.
The point of intersection is (-1+6, 9-8, -16+24) = (5, 1, 8).
Distance = √[(5-(-1))² + (1-9)² + (8-(-16))²] = √[36 + 64 + 576] = √676 = 26.
x = -1 + 3t, y = 9 - 4t, z = -16 + 12t.
Substitute into 2x + 3y - z = 5:
2(-1 + 3t) + 3(9 - 4t) - (-16 + 12t) = 5
-2 + 6t + 27 - 12t + 16 - 12t = 5
41 - 18t = 5
18t = 36, so t = 2.
The point of intersection is (-1+6, 9-8, -16+24) = (5, 1, 8).
Distance = √[(5-(-1))² + (1-9)² + (8-(-16))²] = √[36 + 64 + 576] = √676 = 26.
[JEE Main 2023 · 24 Jan · Shift 1 · Paper-1(B.E./B. Tech.)]