I would say no. Since vector location is subjective, only the direction and magnitude is fixed, two opposite vectors could be overlapping, fully or partial or not at all. To say they are parallel would imply that cannot overlap.
So while it is possible for opposite vectors to be parallel, it is not an assumption that can be made.
Math Instructor
Chat with our AI personalities
It is a vector with the same magnitude (size) but acting in the opposite direction.
You do vector addition.
The result will also be a velocity vector. Draw the first vector. From its tip draw the negative of the second vector ( ie a vector with the same magnitude but opposite direction). The the resultant would be the vector with the same starting point as the first vector and the same endpoint as the second. If the two vectors are equal but opposite, you end up with the null velocity vector.
parallels
equilibrant