Find all vectors v in 2 dimensions having ||v ||=5 where the i -component of v is 3i

Question

vectors:

Answer 1

let the vector be <3,y>
then 3^2 + y^2 = 5^2
y = ±4

so our vectors having a magnitude of 5 of the form <3,y>
are <3,4> and <3,-4>