A0.125 kg frozen hamburger patty has two forces acting on it that determine its horizontal motion. a 2.30 n force pushes it to the left, and a .800 n force pushes it to the right. (a) taking right to be positive, what is the net force acting on it. (b) what is its acceleration

The net force simply the sum of two forces:
Negative and positive are assigned to those forces to show direction because it is a vector.
So, given that left is negative and right is positive;
a)
2.30N - .800N = 1.50 N

Given the equation F = ma, where m= 0.125 (mass) and F = 1.50 (force), we can solve for a (acceleration).
b)
1.50 N = (0.125 kg) a
a = 12.0 ms^-2