Question Number 76302 by john santuy last updated on 26/Dec/19
$${given}\:{vektor}\:{a}=\left(\mathrm{3},{x},−\mathrm{2}\right) \\ $$$${b}=\left(−\mathrm{6},−\mathrm{2},{y}\right)\:.\:{what}\:{the}\:{value}\:{x}\: \\ $$$${and}\:{y}\:{if}\:{a}\:{and}\:{b}\:{are}\:{parallel}? \\ $$
Answered by benjo last updated on 26/Dec/19
$$\mathrm{a}×\mathrm{b}\:=\mathrm{0} \\ $$$$\mathrm{a}×\mathrm{b}\:=\:\left(\mathrm{xy}−\mathrm{4}\right)\mathrm{i}\:−\:\left(\mathrm{3y}−\mathrm{12}\right)\mathrm{j}+\left(\mathrm{6x}−\mathrm{6}\right)\mathrm{k} \\ $$$$=\mathrm{0}.\:\mathrm{therefor}\:\mathrm{y}\:=\:\mathrm{4},\:\mathrm{x}=\mathrm{1} \\ $$