If you would like to simplify |-18-16| - |-8+(-21)|, you can calculate this using the following steps:
|-18-16| - |-8+(-21)| = |-34| - |-29| = 34 - 29 = 5
The correct result would be 5.
Presumably,

. In that case,
(A)
The average rate of change over the interval

is

and over

, it's

(B)

, i.e. the average rate of change over the second interval is 25 times higher. That's to be expected;

is an exponential function. As

gets larger, the rate of change of

gets larger too.
0.6 (y + 3) = 4.8
y+3 =4.8/0.6
y + 3 = 8
y = 8 - 3 = 5
y = 5