Vector Magnitude

2D Vectors

$|\overrightarrow{AB}|=\sqrt{(x_2-x_1{)}^2+(y_2-y_1{)}^2}$

3D Vectors

$|\overrightarrow{AB}|=\sqrt{(x_2-x_1{)}^2+(y_2-y_1{)}^2+(z_2-z_1{)}^2}$