Question

The length of the perpendicular from point (1, 2, 3) to the line $\frac { x - 6 } { 3 } = \frac { y - 7 } { 2 } = \frac { z - 7 } { - 2 }$is

• A. 5
• B. 6
• C. 7
• D. 8

Answer 1

Answer: (C)

7

Answer 2

Projection of [(1, 2, 3) – (6, 7, 7)] along line

$= \frac { - 15 - 10 + 8 } { \sqrt { 17 } } = \frac { - 17 } { \sqrt { 17 } }$

$\therefore$ Distance $= \sqrt { \left( 5 ^ { 2 } + 5 ^ { 2 } + 4 ^ { 2 } \right) - 17 } = \sqrt { 49 } = 7$ .