the position vectors od points A and B woth respect to the original O, are (-8,5)and (12,-5) respectively. point M is the midpoint of AB and N is the midpoint of OA. Fin the coordinate of N and M; the magnitude of NM
A is at (-8 , 5)
B is at (12 ,-5)
so
M is at ( 2 , 0 )
N is at (-4 , 2.5)
|NM| = sqrt(6^2 + 2.5^2)