Question

The lines (x -2)/1 = (y - 3)/1 = (z - 4)/-k and (x - 1)/k = (y -4)/2 = (z - 5)/ 1 are coplanar if
(a) k = 1 or –1 

(b) k = 0 or –3

(c) k = 3 or –3 

(d) k = 0 or –1.

Answer 1

(b) : Using fact, two line

=> k² + 3k = 0
k = 0 or k = –3

Comments

Correct :-)