Answer:
You can define the plane P as BUE plane or BME plane.
Step-by-step explanation:
A plane can be described through a set of points. At first you can define a line. For this you need two collinear point, i.e. point B and U or point B and M. In addition, by specifying a non-collinear point you have a set of coplanar points. This way you have the plane identified.