Question

find the direction vector (d) from the normal vector (n).
n=(3,-1)

Answer 1

Does it matter which number you change the sign for?

Answer 2

To find the direction vector, we just need to swap the components of the normal vector and change one of the signs:

d = (-1, -3)

Therefore, the direction vector is (-1, -3).

Answer 3

No, it doesn't matter which component of the normal vector you change the sign for. You can choose either one and you will get a valid direction vector. Swapping the components and changing the sign of one of them is equivalent to rotating the vector 90 degrees clockwise or counterclockwise.