Since K is in the interior of the angle, this means we can use the angle addition postulate.
Angle LMN = (angle LMK) + (Angle KMN)
Angle LMN = (52 degrees) + (12 degrees)
Angle LMN = (52 + 12) degrees
Angle LMN = 64 degrees
See the attached figure for an example of what this could look like.
