Vectors are equal if they have the same magnitude and direction regardless of where they are. Triangle ABC is isosceles. X is the midpoint of AB, Y is the midpoint of BC and Z is the midpoint of AC.

M is the mid-point of BC and N is the point on OB such that ON:NB = 2:1. Find expressions for these vectors, giving the answers in the simplest form: \(\overrightarrow{ON}\), \(\overrightarrow{OM}\), ...