match each item in column a to an answer in column b.
what property is shown by the equation?
column a
1.–(–33 + 18) = 33 + (–18)
2.–10 + (–15) = –15 + (–10)
3.4 + (29 + 16) = 4 + (16 + 29)
4.–12 + (12 + 27) = (–12 + 12) + 27
column b
a. commutative property
b. associative property
c. opposite of a sum property