To find the answer, you must first expand the expression. To do this, you simply multiply everything by everything, if that makes sense, so:
m × m = m^2
m × 2 = 2m
-5 × m = -5m
-5 × 2 = -10
So you get your answer as m^2 - 3m - 10, which should be one of the trinomials. I hope this helps!
