Q.

The distance of the point (7, 10, 11) from the line x–41=y–40=z–23 along the line x–92=y–133=z–176 is          [2025]

1 14  
2 18  
3 16  
4 12  

Ans.

(1)

Let P≡(7,10,11)

Any point on the line

L1:x–41=y–40=z–23=λ

has coordinates

x=λ+4, y=4, z=3λ+2

i.e., Q(λ+4,4,3λ+2)

∵   Line PQ is parallel to line

L2:x–92=y–33=z–176

⇒ λ+4–72=4–103=3λ+2–116 ⇒ λ=–1

∴   Q(3, 4, –1) is the point on the line L1.

Hence, PQ=16+36+144=14 units.