I believe the answer is ‘1’ :)
First you need to multiple minus in second bracket, also in other side you need to multiple - 3 in bracket

Final answer is 0
Step #1 for both: figure out which interval your x-value fits into.
For f(-2), x=-2 and -2 fits with x ≤ -2, the top interval.
For f(3), x=3 and 3 fits into -2 < x ≤ 3, the middle interval.
Step #2 for both, plug in your x-value to the piece of the function that fits with that interval.
For f(-2), we know x≤-2, so we use 2x+8 to evaluate x=-2.
For f(3), we know -2
f(-2) = 2(-2)+8 = -4+8 = 4
f(3) = (3)^2 -3 = 9-3 = 6
Addition: -9 + -2 = -11
Substraction: -9 - 2 = -11
The answer is 78/7 which is 11 1/7