This is what the problem is saying:
IS 23,567-(12,458+2) +2 equivalent to 23,567-12,458
If we check the first part, we get
23,567-(12,458+2) +2
=23,567-(12,460)+2
=11109
However, if we try the straightforward subtraction
23,567-12,458
=11109
This shows that her method is correct, even though it is a bit long.
In addition to this, if you've learned it, distributive property shows that we can change 23,567-(12,458+2) +2 into 23,567- 12,458 - 2 +2. Then, we can easily cancel out the -2 and +2 to get the regular subtraction expression 23,567-12,458
