A net change in math is the total of all of the changes completed throughout the solving of a problem. The net change is reflected in a numerical amount and can be positive, negative or at zero.
An example of net change can be seen in the equation: X - 5 + 2 = 4. This equation can be simplified and written as: X - 3 = 4. The net change here is - 3 because the person solving the equation will need to subtract three from X in order to get 4. The net change is the sum total of the two changes to X, which are subtracting 5 and adding 2.
When teaching young children how to complete basic problems, many instructors will show the children how to undo net change in order to figure out he problem. In the example provided above, the children can see that the net change is - 3, which means that X must have 3 more than the solution's answer so that the 3 can be taken away or subtracted. This will lead the child to look at the solution, which is 4 and to add 3 more to the solution in order to get X. By the undo net change method, the X is 7. This is correct.