Answer: D. -5m+2m
-5m+2m= -3m
A coefficient is the numerical value in front of the variable, in this case the letter m is the variable. All this means is no matter what the value of m is, it is always multiplied by -3 in this instance. And the variable just represents something you are using an equation to solve for its value. Hope this helps. Any questions please feel free to ask me. Thanks.