Answer:
common difference = 4
Explanation:
common difference is the difference between the successive term and its preceding term.
let's take the successive term of -20 that is - 16
common difference (d) = successive term - preceeding term
= -16 -(-20)
= -16 + 20
= 4
if we take the successive term of -16 that is -12
we'll get the same common difference.
d = -12 -(-16)
d = -12 + 16
d = 4
this means that the common difference for an AP remains constant.