Hey there! :D
When there are two lines (parallel) that are cut by a transversal, corresponding angles form. These are angles that are in the same position on the same side. m<2 is corresponding to the angle that equals 38 degrees. They are congruent and have the same measure.
m<2= 38 degrees
Remember, this only works because the problem said that line L and M are parallel.
I hope this helps!
~kaikers