Answer:
15
Step-by-step explanation:
If this is an arithmetic progression, then there is a common difference.
-3-18 = -21
-21/3 = -7
18 - 7 = x
x = 11
11 - 7 = y
y = 4
4 - 7 = -3
x + y
11 + 4 = 15
5 is the correct answer I believe
5 to 8 right or there more
I was to tired to write it down
Answer:
x=10, y=-10
Step-by-step explanation:
