A) x + 8 = 28
x = 28 - 8
x = 20
B) y - 4 = 30
y = 30 + 4
y = 34
C) s + 2s = 36
3s = 36
s = 12
D) t - t + 4t = 16
4t = 16
t = 4
E) 5a = 15
a = 3
F) 8x - x = 21
7x = 21
x = 3

<h3><em>KemberlyJ</em></h3>
Answer:
D inequality sign always open up to a smaller number
Step-by-step explanation:
If the series is A B C D then the next one is E
The answer is -4.
i hope it helps you!