Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
COMEDK2023Morning ShiftMathematicsThree Dimensional GeometryActual

If two lines L₁: x-1 2 = y+1 3 = z-1 4 and L₂: x-3 1 = y-k 2 =z intersect at a point, then 2 k is equal to

Options

  1. A9
  2. B9 2
  3. C1
  4. D1 2

Correct answer

A. 9

Step-by-step solution

The lines are given by L₁: x-1 2 = y+1 3 = z-1 4 = and L₂: x-3 1 = y-k 2 = z 1 = . Any point on L₁ is (2 + 1, 3 - 1, 4 + 1) and any point on L₂ is ( + 3, 2 + k, ) . Since the lines intersect, there exist and such that: 2 + 1 = + 3 2 - = 2 (1) 3 - 1 = 2 + k 3 - 2 = k + 1 (2) 4 + 1 = (3) Substituting (3) into (1): 2 - (4 + 1) = 2 -2 = 3 = - 3 2 . From (3), = 4(- 3 2 ) + 1 = -6 + 1 = -5 . Substituting = - 3 2 and = -5 into (2): 3(- 3 2 ) - 2(-5) = k + 1 - 9 2 + 10 = k + 1 11 2 = k + 1 k = 9 2 . Therefore, 2k = 2 9 2 =

Practice Three Dimensional Geometry on Quantrex Academy →

More from Three Dimensional Geometry

The circum radius of the triangle formed by the points (2,-1,1),(1,-3,-5) and (3,-4,-4) is 2025Let A (2,3,5), B (-1,3,2), C ( , 5, ) be the vertices of ABC . If the median through the vertex A is equally inclined to the coordinate axes, then 2025Equation of the plane passing through the origin and perpendicular to the planes x+2 y-z=1 and 3 x-4 y+z=5 is 2025If the line joining the points i +2 j and j -2 k intersects the plane passing through the points 2 i - j , 2 j +3 k and k -2 i at r , then r ( i + j + k )= 2025The vector equation of a plane passing through the line of intersection of the planes r ( i -2 k )=3, r (2 j + k )=5 and the point i +2 j +3 k is 2025The points A (-1,2,3), B (2,-3,1), C (3,1,-2) 2025The direction cosines of the line making angles 4 , 3 and (0 < < 2 ) respectively with X , Y and Z axes are 2025If the equation of the plane passing through the point (3,2,5) and perpendicular to the planes 2 x-3 y+5 z=7 and 5 x+2 y-3 z=11 is x+b y+c z+d=0 , then 2 b+3 c+d= 2025 Full Three Dimensional Geometry list All COMEDK PYQs