Your vector will be 10 times the unit vector in that direction. The unit vector is found by dividing the given vector by its length.
|| <3, -2> || = √(3² +(-2)²) = √13
Your vector of length 10 is then
... V = (10/√13)<3, -2> = <(30/13)√13, (-20/13)√13> ≈ <8.32, -5.55>
