### A good answer might be:

The vector is the hypotenuse of a 3-4-5 right triangle,
so its length is 5.
The unit vector is:

1/5 (3,4)^{T} = (3/5, 4/5)^{T} = (0.6, 0.8)^{T}

# Direction of a Unit Vector

Scaling changes the length of a vector
but not its direction.
If **v**_{u} is the unit vector corresponding to **v**,
then **v**_{u} and **v** have the same orientation.

This sounds plausible, but a demonstration might not hurt:

Start with **v** = (3, 4)^{T} as above.
Form **v**_{u} = (3/5, 4/5)^{T}.
The direction of **v** is arc tan( 4/3 ).
The direction of **v**_{u} is
arc tan( (4/5) / (3/5) ) =
arc tan( (4/5) * (5/3) ) =
arc tan( 4/3 ).