You can put this solution on YOUR website! Try this:
The factor will be of the form (m+a)(m+b) where:
(a)(b) = +48
a + b = -14
The obvious candidates for a and b are 6 and 8, but since you need their sum to be -14, then -6 and -8 would be more logical choices. Let's try them, using FOIL.
Simplifying, you get
The factors are: (m-6)(m-8)