Final answer:
The question involves a mathematical equation that requires algebraic manipulation, indicating this is a mathematics problem suitable for a high school level.
Step-by-step explanation:
The expression given by the student, N = -m^2 + (3d/b) - m + (b/3d), signifies a mathematical equation with variables and constants. This pertains to algebra, which is a branch of mathematics. The student may need to simplify the equation, solve for a particular variable, or perhaps substitute given values to find the value of N.