Given a = (1,5, - 1), B = (- 2,3,5), if (KA + b) is parallel (a-3b), find K

Given a = (1,5, - 1), B = (- 2,3,5), if (KA + b) is parallel (a-3b), find K

Ka + b =(k-2,5k+3,-k+5)
(a-3b)=(7,-4,-16)
Ka + B is parallel to a-3b, so the corresponding terms are proportional
(k-2)/7=(5k+3)/(-4)=(-k+5)/(-16)
The solution is k = - 1 / 3