Question

What is the m 12 years ago

Answer 1

do you have a diagram?

Answer 2

i am assuming you are studying geometry
m < DBC i think is involving angles

so all means is that angle m is less than DBC (measure in degree or radians)

Answer 3

No No NO this < in geometry means angle Not less than and if you are talking about angles m < DBC is talking about the angle made up by points DBC