Question

Write a number sentance that shows why the associative property does not work with subtraction

Answer 1

(5-4)-3 = -2.  If we move the parenthesis, as is defined by what the associative property is, 5-(4-3) = 4.  No matter what, you always approach mathematical equations or expressions using PEMDA.  We have to do what's inside the parenthesis first, which is why we end up with 2 different solutions using subtraction.